Technical Field
[0001] The present invention relates to an air conditioner including an indoor unit having
an indoor heat exchanger and a radiation panel.
Background Art
[0002] As an air conditioner, there has been known one which is connected to an outdoor
unit through a refrigerant circuit, and which includes an indoor unit having therein
an indoor heat exchanger, and a radiation panel provided to a surface of the indoor
unit (e.g., see PTL 1) . In the refrigerant circuit of the air conditioner disclosed
in PTL 1, the indoor heat exchanger and the radiation panel are connected in parallel
with each other.
[0003] JP 2010 216767 A discloses an air conditioner in which a first check valve is provided between the
radiation heat exchanger and the opening/closing valve. When the opening/closing valve
is closed, a small volume of a liquid coolant exists between the opening/closing valve
and the first check valve. Even if the liquid coolant is naturally evaporated and
internal pressure rises, the pressure does not become so high to push and open the
opening/closing valve, thus preventing the generation of chattering.
[0004] JP 2001 090977 A discloses an air-conditioner comprising a compressor; an outdoor heat-exchanger;
a pressure reducer; a refrigerating cycle formed such that indoor heat-exchanger each
having an on-off valve to close at least flow passage of a plurality of flow passages;
an indoor machine body to contain the indoor heat-exchanger at an internal part and
having an air inlet and an air outlet; a blower situated at the body and effecting
service entrance of indoor air to the indoor heat-exchanger; and a heating source
situated at a body and in the air passage of the blower extending from the air inlet,
effecting service entrance of indoor air to the indoor heat-exchanger, to the air
outlet.
[0005] JP 2007 333219 A discloses a multi-type air-conditioning system connects the plurality of indoor units
each having the electronic expansion valve expanding a refrigerant, an evaporator
evaporating the expanded refrigerant, and a refrigerant passage allowing the refrigerant
to flow through them, to an outdoor unit. The multi-type air-conditioning system comprises
an inlet side temperature sensor measuring an inlet side refrigerant temperature t1
of the evaporator of each indoor unit; an outlet side temperature sensor measuring
an outlet side refrigerant temperature t2 of the evaporator of each indoor unit 10;
an indoor temperature sensor measuring the suction air temperature t3 of each indoor
unit; and an expansion valve detecting means detecting the abnormal state of the electronic
expansion valve considering the suction air temperature t3 of the indoor unit in addition
to t1 and t2 when the indoor unit is in a blowing operation state.
Citation List
Patent Literature
[0006] [PTL 1] Japanese Unexamined Patent Publication No.
280762/1993 (Tokukaihei 5-280762)
Summary of Invention
Technical Problems
[0007] In the above described air conditioner, it is possible to provide a valve structure
for adjusting the flow rate of a refrigerant supplied to the radiation panel, on a
downstream side of the radiation panel, during a heating operation. In this air conditioner,
the valve structure is closed during a cooling operation, so that the refrigerant
does not flow in the radiation panel, but flows only in the indoor heat exchanger.
During a warm-air heating operation, the valve structure is closed so that the refrigerant
does not flow in the radiation panel and flows only in the indoor heat exchanger.
During a radiation heating operation, the valve structure is opened and the refrigerant
flows both in the radiation panel and the indoor heat exchanger.
[0008] In the above described refrigerant circuit, various problems may take place when
there is a defect in the valve structure. For example, during the cooling operation,
if the refrigerant flows out of the valve structure which is supposed to be closed,
a low-temperature refrigerant flows into the pipe fitting of the radiation panel and
causes dew condensation on the radiation panel. Further, during the warm-air heating
operation, if the refrigerant leaks from the valve structure which is supposed to
be closed, a high-temperature refrigerant passes the pipe fitting of the radiation
panel causing an increase in the temperature of the radiation panel which is not supposed
to increase. Further, during the radiation heating operation, if the valve structure
is closed, or if the opening degree falls short of a required opening degree, the
temperature of the radiation panel which is supposed to increase does not increase.
These problems attributed to a defect in the valve structure may also take place in
a similar manner, in a circuit where the indoor heat exchanger and the radiation panel
are serially connected.
[0009] In view of the above problems, an objective of the present invention is to provide
an air conditioner capable of detecting occurrence of a defect in the valve structure.
Solution to the Problems
[0010] An air conditioner according to the present invention is defined by claim 1. Dependent
claims relate to preferred embodiments.
[0011] In this air conditioner, occurrence of a defect in the valve structure is detectable
by the defect detector based on the temperature of the radiation panel. This restrains
dew condensation on the radiation panel during the cooling operation and inappropriate
radiation panel temperatures during the warm-air heating operation and the radiation
heating operation, which are attributed to a defect in the valve structure.
[0012] According to some preferred embodiments, the refrigerant circuit includes: a principal
channel in which a decompression structure, an outdoor heat exchanger, and a compressor
are provided in this order; a first channel provided with the indoor heat exchanger,
which connects a branching section provided to the downstream side of the compressor
in the principal channel with a merging section provided to the upstream side of the
decompression structure during the heating operation; and a second channel provided
with the radiation panel, which connects the branching section and the merging section
with the first channel in parallel; and wherein the valve structure is provided between
the radiation panel and the merging section in the refrigerant circuit.
[0013] Note that the "the valve structure is provided between the radiation panel and the
merging section in the refrigerant circuit" encompasses cases where the valve structure
is provided to the merging section.
[0014] In this air conditioner in which the first channel having the indoor heat exchanger
and the second channel having the radiation panel are connected in parallel with each
other, occurrence of a defect in the valve structure is detectable.
[0015] The defect detector may detect occurrence of a defect in the valve structure, if
the refrigerant flows in the radiation panel while the valve structure is in a state
in which the refrigerant does not flow in the radiation panel.
[0016] In this air conditioner, occurrence of a defect in the valve structure is detectable
by the defect detector, if the refrigerant flows in the radiation panel while the
valve structure is in the state where the refrigerant does not flow in the radiation
panel.
[0017] The panel temperature sensor may be provided between the radiator of the radiation
panel and the valve structure, wherein the defect detector detects occurrence of a
defect in the valve structure, based on a temperature detected by the panel temperature
sensor and a temperature detected by the indoor heat exchanger temperature sensor.
[0018] In this air conditioner, the open/close state of the valve structure is detectable
by comparing the temperature detected by the panel temperature sensor with the temperature
detected by the indoor heat exchanger temperature sensor. Thus, occurrence of a defect
in the valve structure is detectable, if the valve structure is opened and the refrigerant
flows in the radiation panel while the valve structure is supposed to be in the state
where the refrigerant does not flow in the radiation panel, or if the valve structure
is closed and the refrigerant does not flow in the radiation panel while the valve
structure is supposed to be in the state where the refrigerant flows in the radiation
panel.
[0019] During the cooling operation, the defect detector may detect occurrence of a defect
in the valve structure, when a pressure in the indoor heat exchanger is at or lower
than a predetermined value.
[0020] This air conditioner brings about the following effect. Namely, when the pressure
(low pressure) in the indoor heat exchanger is not sufficiently lowered during the
cooling operation, the difference between the indoor temperature and the temperature
detected by the indoor heat exchanger temperature sensor is small. In such a case,
the temperature detected by the panel temperature sensor and the temperature detected
by the indoor heat exchanger temperature sensor are close to each other, even when
the valve structure is properly closed and the refrigerant does not flow in the radiation
panel. Therefore, even though there is no defect in the valve structure, there is
a possibility of misdetection that the refrigerant is flowing in the radiation panel
due to a defect in the valve structure. In view of this, misdetection of defect in
the valve structure is restrained by excluding such a case.
[0021] The air conditioner preferably includes an indoor temperature sensor configured to
detect an indoor temperature, wherein the defect detector detects occurrence of a
defect in the valve structure, when a difference between a temperature detected by
the indoor temperature sensor and a temperature detected by the indoor heat exchanger
temperature sensor is a predetermined value or greater.
[0022] In this air conditioner, misdetection of a defect in the valve structure is restrained
by excluding cases where the difference between the temperature detected by the indoor
temperature sensor and the temperature detected by the indoor heat exchanger temperature
sensor is small.
Advantageous Effects
[0023] As hereinabove described, the present invention brings about the following effects.
[0024] With the air conditioner according to the present invention, occurrence of a defect
in the valve structure is detectable by the defect detector based on the temperature
of the radiation panel. This restrains problems such as dew condensation on the radiation
panel during the cooling operation and inappropriate radiation panel temperatures
during the warm-air heating operation and the radiation heating operation, which are
attributed to a defect in the valve structure.
[0025] According to some preferred embodiments, occurrence of a defect in the valve structure
is detectable in an air conditioner in which the first channel having the indoor heat
exchanger and the second channel having the radiation panel are connected in parallel
with each other.
[0026] According to some preferred embodiments, occurrence of a defect in the valve structure
is detectable by the defect detector, if the refrigerant flows in the radiation panel
while the valve structure is in the state where the refrigerant does not flow in the
radiation panel.
[0027] According to some preferred embodiments, the open/close state of the valve structure
is detectable by comparing the temperature detected by the panel temperature sensor
with the temperature detected by the indoor heat exchanger temperature sensor. Thus,
occurrence of a defect in the valve structure is detectable, if the valve structure
is opened and the refrigerant flows in the radiation panel while the valve structure
is supposed to be in the state where the refrigerant does not flow in the radiation
panel, or if the valve structure is closed and the refrigerant does not flow in the
radiation panel while the valve structure is supposed to be in the state where the
refrigerant flows in the radiation panel.
[0028] According to some preferred embodiments, when the pressure (low pressure) in the
indoor heat exchanger is not sufficiently lowered during the cooling operation, the
difference between the indoor temperature and the temperature detected by the indoor
heat exchanger temperature sensor is small. In such a case, the temperature detected
by the panel temperature sensor and the temperature detected by the indoor heat exchanger
temperature sensor are close to each other, even when the valve structure is properly
closed and the refrigerant does not flow in the radiation panel. Therefore, even though
there is no defect in the valve structure, there is a possibility of misdetection
that the refrigerant is flowing in the radiation panel due to a defect in the valve
structure. In view of this, misdetection of defect in the valve structure is restrained
by excluding such a case.
[0029] According to some preferred embodiments, misdetection of a defect in the valve structure
is restrained by excluding cases where the difference between the temperature detected
by the indoor temperature sensor and the temperature detected by the indoor heat exchanger
temperature sensor is small.
Brief Description of Drawings
[0030]
[FIG. 1] FIG. 1 is a circuit diagram illustrating a schematic configuration of an
air conditioner related to an embodiment of the present invention, and shows a flow
of a refrigerant during a cooling operation and a warm-air heating operation.
[FIG. 2] FIG. 2 is a circuit diagram illustrating a schematic configuration of the
air conditioner related to the embodiment of the present invention, and shows a flow
of the refrigerant during the radiation heating operation.
[FIG. 3] FIG. 3 is a perspective view of an indoor unit illustrated in FIG. 1 and
FIG. 2.
[FIG. 4] FIG. 4 is a cross sectional view of the indoor unit taken along the line
IV-IV in FIG. 3.
[FIG. 5] FIG. 5 is a block diagram illustrating a schematic configuration of a controller
controlling the air conditioner.
[FIG. 6] FIG. 6 is a graph explaining a condition for detecting a defect by a defect
detector illustrated in FIG. 5, during the cooling operation, taking into account
prevention of misdetection.
[FIG. 7] FIG. 7 is a graph explaining a condition for detecting a defect by the defect
detector illustrated in FIG. 5, during the warm-air heating operation.
[FIG. 8] FIG. 8 is a graph explaining a condition for detecting a defect by the defect
detector illustrated in FIG. 5, during the radiation heating operation.
[FIG. 9] FIG. 9 is a flowchart showing steps of a defect detecting process executed
by the defect detector illustrated in FIG. 5 during the cooling operation.
[FIG. 10] FIG. 10 is a flowchart showing steps of a defect detecting process executed
by the defect detector illustrated in FIG. 5 during the warm-air heating operation.
[FIG. 11] FIG. 11 is a flowchart showing steps of a defect detecting process executed
by the defect detector illustrated in FIG. 5 during the radiation heating operation.
[FIG. 12] FIG. 12 is a circuit diagram illustrating a schematic configuration of an
air conditioner related to a modification of the embodiment.
Description of Embodiments
[0031] Hereinafter, an air conditioner 1 according to an embodiment of the present invention
will be described.
<Entire Configuration of Air Conditioner 1>
[0032] As illustrated in Figs. 1 and 2, the air conditioner 1 of the embodiment includes
an indoor unit 2 that is installed in a room, an outdoor unit 6 that is installed
out of the room, and a remote controller 9 (see FIG. 5) . The indoor unit 2 includes
an indoor heat exchanger 20 disposed to oppose to an indoor fan 21, a radiation panel
30, an indoor motor-operated valve 23, and an indoor temperature sensor 24 that detects
an indoor temperature. The outdoor unit 6 includes a compressor 60, a four-way valve
61, an outdoor heat exchanger 62, an outdoor fan 63 that is disposed near the outdoor
heat exchanger 62, and an outdoor motor-operated valve 64 (a decompression structure).
[0033] The air conditioner 1 includes a refrigerant circuit 10 that connects the indoor
unit 2 and the outdoor unit 6 to each other. The refrigerant circuit 10 includes a
principal channel 11 in which the outdoor motor-operated valve 64, the outdoor heat
exchanger 62, and the compressor 60 are provided in this order. An intake-side pipe
fitting and a discharge-side pipe fitting of the compressor 60 are connected to the
four-way valve 61. A branching section 10a is provided in a portion that becomes a
downstream side of the compressor 60 in the principal channel 11 during a heating
operation (as described later, when a refrigerant is flowing in a direction indicated
by a solid-line arrow in FIG. 1 in the refrigerant circuit 10), and a merging section
10b is provided in a portion that becomes an upstream side of the outdoor motor-operated
valve 64. The refrigerant circuit 10 also includes a first channel 12 and a second
channel 13. The first channel 12 connects the branching section 10a and the merging
section 10b to each other, and the indoor heat exchanger 20 is provided in the first
channel 12. The second channel 13 is connected in parallel with the first channel
12 between the branching section 10a and merging section 10b, and the radiation panel
30 is provided in the second channel 13.
[0034] An indoor motor-operated valve (valve structure) 23 is provided between the radiation
panel 30 and the merging section 10b in the second channel 13. A panel incoming temperature
sensor 25 and a panel outgoing temperature sensor 26 are attached to both sides of
the radiation panel 30 in the second channel 13. More specifically, the panel incoming
temperature sensor 25 is provided in a pipe fitting and is on the upstream side of
a radiator 35, which will be described later, (see FIG. 4) of the radiation panel
30 during the heating operation. The panel outgoing temperature sensor 26 is provided
in the pipe fitting and is on the downstream side of the radiator 35 of the radiation
panel 30 and upstream side of the indoor motor-operated valve 23, during the heating
operation.
[0035] In the refrigerant circuit 10, an accumulator 65 is interposed between an intake
side of the compressor 60 and the four-way valve 61, and a discharge temperature sensor
66 is attached between a discharge side of the compressor 60 and the four-way valve
61. An outdoor heat exchanger temperature sensor 68 is attached to the outdoor heat
exchanger 62.
[0036] The indoor heat exchanger 20 includes the pipe fitting, which constitutes a part
of the refrigerant circuit 10, and an indoor heat exchanger temperature sensor 27
is attached to the indoor heat exchanger 20. The indoor heat exchanger 20 is disposed
on a windward side of the indoor fan 21. Air heated or cooled by heat exchange with
the indoor heat exchanger 20 is blown as warm wind or cool wind into the room by the
indoor fan 21, thereby performing warm-air heating or cooling.
[0037] The radiation panel 30 is disposed on a surface side of the indoor unit 2, and includes
a panel pipe fitting 36 which is a pipe fitting constituting a part of the refrigerant
circuit 10. Heat of the refrigerant flowing in the panel pipe fitting 36 is radiated
into the room to perform radiation heating. The indoor motor-operated valve 23 is
provided in order to adjust a flow rate of the refrigerant supplied to the radiation
panel 30. Controlling opening and closing of the indoor motor-operated valve 23 enables
switching over between a state where the refrigerant flows in the panel pipe fitting
36 of the radiation panel 30 and a state where the refrigerant does not flow in the
panel pipe fitting 36 of the radiation panel 30.
[0038] The air conditioner 1 of the embodiment is capable of performing a cooling operation,
a warm-air heating operation, and a radiation heating operation. The cooling operation
is an operation which performs cooling by causing the refrigerant to flow not in the
radiation panel 30, but in the indoor heat exchanger 20, whereas the warm-air heating
operation is an operation which performs warm-air heating by causing the refrigerant
to flow not in the radiation panel 30, but in the indoor heat exchanger 20. The radiation
heating operation is an operation which performs radiation heating by causing the
refrigerant to flow in the radiation panel 30, while performing warm-air heating by
causing the refrigerant to flow in the indoor heat exchanger 20.
[0039] A flow of the refrigerant in the refrigerant circuit 10 during each operation will
be described with reference to Figs. 1 and 2.
During the cooling operation, the indoor motor-operated valve 23 is closed, and the
four-way valve 61 is switched to a state indicated by a broken line in FIG. 1. Therefore,
as indicated by a broken-line arrow in FIG. 1, the high-temperature, high-pressure
refrigerant discharged from the compressor 60 flows in the outdoor heat exchanger
62 through the four-way valve 61. The refrigerant condensed by the outdoor heat exchanger
62 flows in the indoor heat exchanger 20 after being decompressed by the outdoor motor-operated
valve 64. The refrigerant vaporized by the indoor heat exchanger 20 flows in the compressor
60 through the four-way valve 61 and accumulator 65. Note that, with the indoor motor-operated
valve 23 being closed, the refrigerant decompressed by the outdoor motor-operated
valve 64 is kept from flowing towards the radiation panel 30 beyond the indoor motor-operated
valve 23 in the second channel 13.
[0040] During the warm-air heating operation, the indoor motor-operated valve 23 is closed,
and the four-way valve 61 is switched to the state indicated by the solid line in
FIG. 1. Therefore, as indicated by the solid-line arrow in FIG. 1, the high-temperature,
high-pressure refrigerant discharged from the compressor 60 flows in the indoor heat
exchanger 20 through the four-way valve 61. The refrigerant condensed by the indoor
heat exchanger 20 flows in the outdoor heat exchanger 62 after being decompressed
by the outdoor motor-operated valve 64. The refrigerant vaporized by the outdoor heat
exchanger 62 flows in the compressor 60 through the four-way valve 61 and accumulator
65. With the indoor motor-operated valve 23 being closed, the refrigerant discharged
from the compressor 60 does not flow onto the side of the merging section 10b beyond
the indoor motor-operated valve 23 in the second channel 13. That is, in the second
channel 13, the refrigerant is accumulated on the upstream side of the indoor motor-operated
valve 23.
[0041] During the radiation heating operation, the indoor motor-operated valve 23 is opened,
and the four-way valve 61 is switched to a state indicated by a solid line in FIG.
2. Therefore, as indicated by a solid-line arrow in FIG. 2, the high-temperature,
high-pressure refrigerant discharged from the compressor 60 flows in the indoor heat
exchanger 20 and radiation panel 30 through the four-way valve 61. The refrigerant
condensed by the indoor heat exchanger 20 and radiation panel 30 flows in the outdoor
heat exchanger 62 after being decompressed by the outdoor motor-operated valve 64.
The refrigerant vaporized by the outdoor heat exchanger 62 flows in the compressor
60 through the four-way valve 61 and accumulator 65.
<Configuration of Indoor Unit 2>
[0042] A configuration of the indoor unit 2 will be described below. As illustrated in FIG.
3, the indoor unit 2 of the embodiment has a rectangular solid shape as a whole, and
is installed near a floor surface in the room. In the embodiment, the indoor unit
2 is attached to a wall surface while floating from the floor surface by about 10
cm. Hereinafter, a direction in which the indoor unit 2 projects from the attached
wall is referred to as a "front", and the opposite direction is referred to as a "rear".
A right-left direction in FIG. 3 is simply referred to as a "horizontal direction",
and an up-down direction is simply referred to as a "vertical direction".
[0043] As illustrated in FIG. 4, the indoor unit 2 mainly includes a casing 4, internal
devices, such as the indoor fan 21, the indoor heat exchanger 20, an outlet unit 46,
and an electric component unit 47, which are accommodated in the casing 4, and a front
grill 42. As described in detail later, the casing 4 includes a principal inlet 4a
that is formed in a lower wall of the casing 4 and auxiliary inlets 4b and 4c that
are formed in a front wall of the casing 4. An outlet 4d is formed in an upper wall
of the casing 4. In the indoor unit 2, by driving the indoor fan 21, while the air
near the floor surface is drawn through the principal inlet 4a, the air is also drawn
through the auxiliary inlets 4b and 4c. The indoor heat exchanger 20 heats or cools
the drawn air to perform conditioning. Then the post-conditioning air is blown from
the outlet 4d and returned to the room.
[0044] The casing 4 includes a body frame 41, an outlet cover 51, the radiation panel 30,
and an opening-closing panel 52. As described in detail later, the outlet cover 51
includes a front panel section 51a, and the radiation panel 30 includes a radiation
plate 31. The front panel section 51a of the outlet cover 51, the radiation plate
31 of the radiation panel 30, and the opening-closing panel 52 are disposed so as
to be flush with one another in a front surface of the casing 4, and the front panel
section 51a, the radiation plate 31, and the opening-closing panel 52 constitute a
front panel 5. As illustrated in FIG. 3, a power button 48 and an emission display
section 49 that indicates an operation status are provided in an upper right end portion
of the front panel 5, namely, a right end portion of the front panel section 51a of
the outlet cover 51.
[0045] The body frame 41 is one that is attached to a wall surface, and the body frame 41
supports various internal devices described above. The front grill 42, the outlet
cover 51, the radiation panel 30, and the opening-closing panel 52 are attached to
the front surface of the body frame 41 while the body frame 41 supports the internal
devices. The outlet cover 51 is attached to an upper end portion of the body frame
41, and the outlet 4d that is of a horizontally long rectangular opening is formed
on the upper wall of the outlet cover 51. The radiation panel 30 is attached below
the outlet cover 51, and the opening-closing panel 52 is attached below the radiation
panel 30. The principal inlet 4a that is the horizontally long opening is formed between
a lower front end of the body frame 41 and a lower end of the opening-closing panel
52.
[0046] Each internal device accommodated in the casing 4 will be described below.
The indoor fan 21 is disposed slightly above a central portion in a height direction
of the casing 4 such that an axial direction of the indoor fan 21 is aligned with
the horizontal direction. The indoor fan 21 draws the air from the lower front and
flows the air to the upper rear.
[0047] The indoor heat exchanger 20 is disposed in substantially parallel with the front
panel 5. The indoor heat exchanger 20 includes a front heat exchanger 20a that is
opposed to the rear surface of the front panel 5 and a rear heat exchanger 20b that
is upwardly inclined toward the rear surface from a vicinity of the lower end portion
of the front heat exchanger 20a. The front heat exchanger 20a is disposed in front
of the indoor fan 21, and its upper half is opposed to the indoor fan 21. The rear
heat exchanger 20b is disposed below the indoor fan 21 and is opposed to the indoor
fan 21. That is, the indoor heat exchanger 20 as a whole has a substantially V-shape,
and is disposed in such a manner as to oppose to the front and lower side of the indoor
fan 21.
[0048] A horizontally extending drain pan 22 is disposed below the indoor heat exchanger
20. Further, below the drain pan 22 is arranged an electric component unit 47.
[0049] The outlet unit 46 is disposed above the indoor fan 21, and guides the air blown
from the indoor fan 21 to the outlet 4d formed in the upper wall of the casing 4.
The outlet unit 46 has a horizontal flap 46a disposed nearby the outlet 4d. The horizontal
flap 46a changes the direction of an air flow from the outlet 4d relative to the vertical
direction, and open or closes the outlet 4d.
[0050] As described above, the front grill 42 is attached to the body frame 41 so as to
cover the body frame 41 to which such internal devices as the indoor heat exchanger
20, the indoor fan 21, the outlet unit 46, and the electric component unit 47 are
attached. More specifically, the front grill 42 is attached to the body frame 41 so
as to cover a range from the substantially central portion in the vertical direction
of the front heat exchanger 20a to the lower end of the body frame 41. The front grill
42 includes a filter retaining section 42a and an inlet grill 42b disposed in the
principal inlet 4a.
[0051] To the filter retaining section 42a are attached a lower filter 43 and an upper filter
44. As shown in FIG. 4, the lower filter 43 held by the filter retaining section 42a
extends downward from substantially the central portion of the front heat exchanger
20a relative to the vertical direction, and its lower end portion is tilted in a direction
obliquely backside. The lower end of the lower filter 43 is positioned nearby the
rear end of the principal inlet 4a. Further, the upper filter 44 extends upwards from
the substantially central portion of the front heat exchanger 20a relative to the
vertical direction. With the lower filter 43 and the upper filter 44, the space between
the front heat exchanger 20a and the front panel 5 is divided relative to the front-rear
direction.
[0052] The outlet cover 51 covers the outlet unit 46. As described above, the outlet 4d
is formed in the upper wall of the outlet cover 51. The front panel section 51a is
provided in the front surface of the outlet cover 51. The front panel section 51a
has the horizontally long rectangular shape.
[0053] The radiation panel 30 has the horizontally long, substantially rectangular shape.
The radiation panel 30 mainly includes an aluminum radiation plate 31 and a resin
heat-insulating cover 32 attached to the rear surface of the radiation plate 31. The
radiation plate 31 is positioned below the front panel section 51a of the outlet cover
51. As illustrated in FIG. 4, the panel pipe fitting 36 that is of the part of the
pipe fitting constituting the refrigerant circuit 10 is attached to the rear surface
of the radiation plate 31. The portion of the radiation panel 30 where the radiation
plate 31 and the panel pipe fitting 36 are in contact with each other, are the portions
serving as the radiator 35.
[0054] The opening-closing panel 52 is detachably attached to the lower portion of the radiation
plate 31 of the radiation panel 30. The opening-closing panel 52 has the horizontally
long rectangular shape. As illustrated in FIG. 4, the vertical position at the upper
end of the opening-closing panel 52 has the substantially same level as the upper
end of the front grill 42. As described above, the lower end of the opening-closing
panel 52 constitutes the part of the principal inlet 4a. Accordingly, the front grill
42 is exposed by detaching the opening-closing panel 52, so that the lower filter
43 and upper filter 44, which are attached to the filter retaining section 42a of
the front grill 42, can be detached.
<Remote Controller 9>
[0055] With the remote controller 9, a user is able to start or stop the operation of the
air conditioner 1, set the operation mode, set the target indoor temperature (indoor
setting temperature), or set the blowing air quantity, or the like.
<Controller 7>
[0056] Next, the controller 7 for controlling the air conditioner 1 is described with reference
to FIG. 5.
As shown in FIG. 5, the controller 7 has a storage 70, an indoor motor-operated valve
controller 72, a defect detector 73, an indoor fan controller 74, a compressor controller
75, and an outdoor motor-operated valve controller 76.
[0057] The storage 70 stores various operation settings related to the air conditioner 1,
a control program, a data table necessary for running the control program, or the
like. The operation settings include user-setting set by a user operating the remote
controller 9, such as target indoor temperature (indoor setting temperature), and
a presetting which is set in advance in the air conditioner 1. In the air conditioner
1 of the embodiment, the target temperature range of the radiation panel 30 is set
to a predetermined temperature range (e.g., 50 to 55°C) . The target temperature range
of the radiation panel 30 however may be set by operating the remote controller 9.
[0058] The indoor motor-operated valve controller 72 controls the opening degree of the
indoor motor-operated valve 23. During the cooling operation or the warm-air heating
operation, the indoor motor-operated valve controller 72 closes the indoor motor-operated
valve 23. Further, during the radiation heating operation, the indoor motor-operated
valve controller 72 controls the opening degree of the indoor motor-operated valve
23 based on the temperature of the radiation panel 30. Specifically, a surface temperature
(predicted value) of the radiation panel 30 is calculated based on a calculated value
of temperatures detected by the panel incoming temperature sensor 25 and the panel
outgoing temperature sensor 26. The opening degree of the indoor motor-operated valve
23 is controlled so that this surface temperature of the radiation panel 30 (hereinafter,
simply referred to as radiation panel temperature) is within a panel target temperature
range (e.g. 50 to 55°C). Note that when the value detected by the panel incoming temperature
sensor 25 is a predetermined value (e.g., 80°C) or more, the indoor motor-operated
valve 23 is closed.
[0059] The defect detector 73 detects occurrence of a defect in the indoor motor-operated
valve 23, based on the temperature of the radiation panel 30. That is, during the
cooling operation and during the warm-air heating operation, the defect detector 73
detects occurrence of a defect in the indoor motor-operated valve 23, if the refrigerant
flows out of the indoor motor-operated valve 23 which is supposed to be closed and
flows in the panel pipe fitting 36 of the radiation panel 30. Further, during the
radiation heating operation, occurrence of a defect in the indoor motor-operated valve
23 is detected when the indoor motor-operated valve 23 is completely closed, and the
refrigerant does not flow in the panel pipe fitting 36 of the radiation panel 30.
Specifically, during the cooling operation, the defect detector 73 detects occurrence
of a defect in the indoor motor-operated valve 23, based on a temperature (hereinafter,
simply referred to as indoor temperature Ta) detected by the indoor temperature sensor
24, a temperature (hereinafter, simply referred to as panel pipe fitting temperature
TP) detected by the panel outgoing temperature sensor 26, and a temperature (hereinafter,
simply referred to as indoor heat exchanger temperature Te) detected by the indoor
heat exchanger temperature sensor 27. Further, during the warm-air heating operation
and during the radiation heating operation, occurrence of a defect in the indoor motor-operated
valve 23 is detected based on the panel pipe fitting temperature TP and the indoor
heat exchanger temperature Te.
[0060] When a defect occurs in the indoor motor-operated valve 23 during the cooling operation,
and the refrigerant flows out of the indoor motor-operated valve 23 which is supposed
to be closed, the low-temperature refrigerant having flown from the merging section
10b into the second channel 13 flows into the pipe fitting on the downstream side
(the side of radiation panel 30) of the indoor motor-operated valve 23. Therefore,
the panel pipe fitting temperature TP detected by the panel outgoing temperature sensor
26 drops to a temperature at or below the indoor heat exchanger temperature Te detected
by the indoor heat exchanger temperature sensor 27 provided in the indoor heat exchanger
20 where heat exchanging takes place. In other words, a defect in the indoor motor-operated
valve 23 is detected by the defect detector 73 on condition that the following (Formula
1) is satisfied.
[0061] In the embodiment, the defect in the indoor motor-operated valve 23 is detected only
in cases where the temperature of the refrigerant flowing out of the outdoor motor-operated
valve 64 is sufficiently low and where such a refrigerant, when flowing into the pipe
fitting of the radiation panel 30, may cause dew condensation on the radiation panel
30. Therefore, a defect in the indoor motor-operated valve 23 is detected by the defect
detector 73 on condition that the following (Formula 2) and (Formula 3) are satisfied,
in addition to (Formula 1).
[0062] Additionally, for example, when the outdoor unit 6 is a multi-connectable outdoor
unit which is connectable with a plurality of indoor units, and when the indoor units
connected with the outdoor unit 6 are operated at the same time, the pressure (low
pressure) in the indoor heat exchanger 20 may not sufficiently drop. Since the indoor
temperature Ta, the panel pipe fitting temperature TP, and the indoor heat exchanger
temperature Te are substantially the same temperature in such a case, the above (Formula
1) may be satisfied even though no defect takes place in the indoor motor-operated
valve 23. To prevent such a misdetection, the following (Formula 4) is added to the
above (Formula 1) to (Formula 3) as a condition for the defect detector 73 to detect
that the indoor motor-operated valve 23 is abnormal.
[0063] Note that, when the difference between the indoor temperature Ta and the indoor heat
exchanger temperature Te is less than 5 deg., dew condensation will not take place
on the radiation panel 30 as long as the relative humidity is not more than 80%, even
if the refrigerant is flowing out due to a defect in the indoor motor-operated valve
23.
[0064] Based on the above (Formula 4), a defect detectable area of the indoor motor-operated
valve 23 is only an area (I) shown in FIG. 6. That is, a defect in the indoor motor-operated
valve 23 is not detected in an area (an area indicated by (II) in the figure) where
the indoor heat exchanger temperature Te is higher than the indoor temperature Ta
(i.e., Ta-Te < 0 deg.) and where detection of defect in the indoor motor-operated
valve 23 is not necessary, and in an area (area indicated by (III) in the figure)
where the difference between the indoor temperature Ta and the indoor heat exchanger
temperature Te is relatively small (i.e., 0 deg. ≤ Ta-Te < 5 deg.) and misdetection
of a defect in the indoor motor-operated valve 23 may take place.
[0065] Thus, when the indoor temperature Ta detected by the indoor temperature sensor 24,
the panel pipe fitting temperature TP detected by the panel outgoing temperature sensor
26, and the indoor heat exchanger temperature Te detected by the indoor heat exchanger
temperature sensor 27 satisfy all of the (Formula 1) to (Formula 4) during the cooling
operation, the defect detector 73 detects that the indoor motor-operated valve 23
is abnormal.
[0066] During the warm-air heating operation, if the defect occurs in the indoor motor-operated
valve 23 and the refrigerant flows out of the indoor motor-operated valve 23 which
is supposed to be closed, the high-temperature refrigerant having flown from the branching
section 10a into the second channel 13 flows out of the second channel 13 via the
pipe fitting of the radiation panel 30 and the indoor motor-operated valve 23. Therefore,
the panel pipe fitting temperature TP detected by the panel outgoing temperature sensor
26 increases and becomes equal to or higher than the indoor heat exchanger temperature
Te detected by the indoor heat exchanger temperature sensor 27 provided in the indoor
heat exchanger 20. That is, a defect in the indoor motor-operated valve 23 is detected
by the defect detector 73 on condition that the following (Formula 5) is satisfied.
[0067] Further, in the embodiment, a defect in the indoor motor-operated valve 23 is detected
only in cases where the temperature of the refrigerant discharged from the compressor
60 is relatively high and where the radiation panel 30 has a high temperature of a
certain extent as the refrigerant passes through the pipe fitting in the radiation
panel 30. Therefore, a defect in the indoor motor-operated valve 23 is detected by
the defect detector 73 on condition that the following (Formula 6) and (Formula 7)
are satisfied, in addition to (Formula 5) .
[0068] Considering the relation between the surface temperature of the radiation panel 30
(hereinafter, simply referred to as panel temperature TP0) and the indoor heat exchanger
temperature Te, a defect detectable area of the indoor motor-operated valve 23 is
only an area (an area indicated by (I) in the figure) shown in FIG. 7, where the panel
temperature TP0 is 40°C or higher and where the indoor heat exchanger temperature
Te is 43°C or higher. In other words, a defect in the indoor motor-operated valve
23 is not detected in an area (an area indicated by (II) in the figure) which does
not possibly occur in an actual operation, in which area the panel temperature TP0
is 40°C or higher and the indoor heat exchanger temperature Te is lower than 43°C,
or in an area (an area indicated by (III) in the figure) where the panel temperature
TP0 is lower than 40°C, in which case if a defect is to be detected, there would be
a chance of misdetection of a defect in the indoor motor-operated valve 23.
[0069] In other words, when the panel pipe fitting temperature TP detected by the panel
outgoing temperature sensor 26 and the indoor heat exchanger temperature Te detected
by the indoor heat exchanger temperature sensor 27 satisfy all the above (Formula
5) to (Formula 7) during the warm-air heating operation, the defect detector 73 detects
that the indoor motor-operated valve 23 is abnormal.
[0070] When the indoor motor-operated valve 23 is closed, and there is a defect in the indoor
motor-operated valve 23 during the radiation heating operation, the high-temperature
refrigerant having flowing from the branching section 10a into the second channel
13 is accumulated in the pipe fitting on the upstream side (the side of the radiation
panel 30) of the indoor motor-operated valve 23. Therefore, the panel pipe fitting
temperature TP detected by the panel outgoing temperature sensor 26 does not increase
and the difference between the indoor heat exchanger temperature Te and the panel
pipe fitting temperature TP is increased. That is, a defect in the indoor motor-operated
valve 23 is detected by the defect detector 73 on condition that the following (Formula
8) is satisfied.
[0071] Note that, when the indoor motor-operated valve 23 is completely closed, the indoor
temperature is 10°C, and the indoor heat exchanger temperature is 55°C, the difference
between the indoor heat exchanger temperature Te and the panel pipe fitting temperature
TP is 35 deg.
[0072] Further, in the embodiment, a defect in the indoor motor-operated valve 23 is not
detected if the temperature of the radiation panel 30 shows a certain increase even
though the indoor motor-operated valve 23 is closed. A defect in the indoor motor-operated
valve 23 is detected only if there seems to be no increase in the temperature of the
radiation panel 30. Therefore, a defect in the indoor motor-operated valve 23 is detected
by the defect detector 73 on condition that the following (Formula 9) and (Formula
10) are satisfied, in addition to (Formula 8).
[0073] Considering the relation between the panel temperature TP0 and the indoor heat exchanger
temperature Te, a defect detectable area of the indoor motor-operated valve 23 is
only an area (I) shown in FIG. 8. In other words, a defect in the indoor motor-operated
valve 23 is not detected in an area (an area indicated by (II) in the figure) which
does not possibly occur in an actual operation, in which area the panel temperature
TP0 is higher than the indoor heat exchanger temperature Te (i.e., Te - TP0 < 0 deg.),
or in an area (an area indicated by (III) in the figure) where the difference between
the indoor heat exchanger temperature Te and the panel temperature TP0 is relatively
small (i.e., 0 deg. ≤ Te - TP0 < 35 deg.) and where a defect in the indoor motor-operated
valve 23 is not detectable.
[0074] In other words, when the panel pipe fitting temperature TP detected by the panel
outgoing temperature sensor 26 and the indoor heat exchanger temperature Te detected
by the indoor heat exchanger temperature sensor 27 satisfy all the above (Formula
8) to (Formula 10) during the radiation heating operation, the defect detector 73
detects that the indoor motor-operated valve 23 is abnormal.
[0075] The indoor fan controller 74 controls the rotational frequency of the indoor fan
21 according to the operation mode, the indoor setting temperature, the blowing air
quantity set by the remote controller 9, and the indoor temperature detected by the
indoor temperature sensor 24.
[0076] The compressor controller 75 controls the operation frequency of the compressor 60,
based on the indoor temperature, the indoor setting temperature, the heat exchanger
temperature detected by the indoor heat exchanger temperature sensor 27, and the like.
[0077] The outdoor motor-operated valve controller 76 controls the opening degree of the
outdoor motor-operated valve 64. More specifically, the outdoor motor-operated valve
controller 76 controls the opening degree of the outdoor motor-operated valve 64 so
that the temperature detected by the discharge temperature sensor 66 becomes an optimal
temperature in the operation status. The optimal temperature is determined based on
a calculated value using the indoor heat exchanger temperature and an outdoor heat
exchanger temperature.
<Defect Detecting Process by Defect Detector 73>
[0078] The following describes the steps of a defect detecting process executed by the defect
detector 73 for detecting a defect in the indoor motor-operated valve 23.
[0079] During the cooling operation, as shown in FIG. 9, the indoor temperature Ta detected
by the indoor temperature sensor 24, the panel pipe fitting temperature TP detected
by the panel outgoing temperature sensor 26, and the Te detected by the indoor heat
exchanger temperature sensor 27 are first obtained (step S11). Next, there is determined
whether or not the difference between the indoor temperature Ta and the indoor heat
exchanger temperature Te is 5 deg. or more (step S12). When the difference between
the indoor temperature Ta and the indoor heat exchanger temperature Te is smaller
than 5 deg. (step S12: NO), there is a possibility of misdetection of a defect in
the indoor motor-operated valve 23. Therefore, the process does not proceed to the
next step and returns to step S11.
[0080] On the other hand, when the difference between the indoor temperature Ta and the
indoor heat exchanger temperature Te is at least 5 deg. (step S12: YES), there is
determined whether or not the difference between the panel pipe fitting temperature
TP and the indoor heat exchanger temperature Te is at most 0 deg. (step S13). When
the difference between the panel pipe fitting temperature TP and the indoor heat exchanger
temperature Te is higher than 0 deg. (step S13: NO), it is considered that the indoor
motor-operated valve 23 is properly closed, and there is no refrigerant flowing out.
Therefore, the process does not proceed to the next step, and returns to step S11.
[0081] Further, when the difference between the panel pipe fitting temperature TP and the
indoor heat exchanger temperature Te is 0 deg. or smaller (step S13: YES), it is considered
that the refrigerant is flowing out of the indoor motor-operated valve 23 which is
supposed to be closed. Next, in step S14, there is determined whether the panel pipe
fitting temperature TP is at most 32°C, and there is determined in step S15 whether
the indoor heat exchanger temperature Te is at most 32°C. When the panel pipe fitting
temperature TP is determined as to be higher than the 32°C in step S14 (step S14:
NO), or when the indoor heat exchanger temperature Te is determined as to be higher
than 32°C in step S15 (step S15: NO), it is considered that dew condensation will
not take place on the radiation panel 30. Therefore, the process does not proceed
to the next step and returns to step S11.
[0082] On the other hand, when the panel pipe fitting temperature TP is determined as to
be 32°C or lower in step S14 (step S14: YES), or when the indoor heat exchanger temperature
Te is determined as to be 32°C or lower in step S15 (step S15: YES), occurrence of
a defect in the indoor motor-operated valve 23 is detected (step S16).
[0083] During the warm-air heating operation, as shown in FIG. 10, the panel pipe fitting
temperature TP detected by the panel outgoing temperature sensor 26, the Te detected
by the indoor heat exchanger temperature sensor 27 are first obtained (step S21).
Next, there is determined whether the difference between the indoor heat exchanger
temperature Te and the panel pipe fitting temperature TP is at most 0 deg. (step S22).
Here, when the difference between the indoor heat exchanger temperature Te and the
panel pipe fitting temperature TP is greater than 0 deg. (step S22: NO), it is considered
that the indoor motor-operated valve 23 is properly closed, and there is no refrigerant
flowing out. Therefore, the process does not proceed to the next step and returns
to step S21.
[0084] Further, when the difference between the indoor heat exchanger temperature Te and
the panel pipe fitting temperature TP is at most 0 deg. (step S22: YES), it is considered
that the refrigerant is flowing out of the indoor motor-operated valve 23 which is
supposed to be closed. Next, there is determined whether the panel pipe fitting temperature
TP is 43°C or higher in step S23, and there is determined whether the indoor heat
exchanger temperature Te is 43°C or higher in step S24. When the panel pipe fitting
temperature TP is determined as to be lower than 43°C in step S23 (step S23: NO),
or when the indoor heat exchanger temperature Te is determined as to be lower than
43°C in step S24 (step S24: NO), it is considered that the temperature of the radiation
panel 30 will not increase so much (that detection of a defect in the indoor motor-operated
valve 23 is necessary) . Therefore, the process does not proceed to the next step
and returns to step S21.
[0085] On the other hand, when the panel pipe fitting temperature TP is determined as to
be 43°C or higher in step S23 (step S23: YES), or when the indoor heat exchanger temperature
Te is determined as to be 43°C or higher in step S24 (step S24: YES), occurrence of
a defect in the indoor motor-operated valve 23 is detected (step S25) .
[0086] During the radiation heating operation, as shown in FIG. 11, the panel pipe fitting
temperature TP detected by the panel outgoing temperature sensor 26, the Te detected
by the indoor heat exchanger temperature sensor 27 are first obtained (step S31).
Next, there is determined whether the difference between the indoor heat exchanger
temperature Te and the panel pipe fitting temperature TP is 35 deg. or greater (step
S32). When the difference between the indoor heat exchanger temperature Te and the
panel pipe fitting temperature TP is determined as to be smaller than 35 deg. (step
S22: NO), it is considered that the indoor motor-operated valve 23 is opened. Therefore,
the process does not proceed to the next step and returns to step S31.
[0087] Further, when the difference between the indoor heat exchanger temperature Te and
the panel pipe fitting temperature TP is 35 deg. or greater (step S32: YES), it is
considered that the indoor motor-operated valve 23 which is supposed to be opened
is closed. Next, there is determined whether the panel pipe fitting temperature TP
is at most 60°C in step S33, and there is determined whether the indoor heat exchanger
temperature Te is at most 60°C or lower in step S34. When the panel pipe fitting temperature
TP is determined as to be higher than 60°C in step S33 (step S33: NO), or when the
indoor heat exchanger temperature Te is determined as to be higher than 60°C in step
S34 (step S34: NO), the process does not proceed to the next step and returns to step
S31.
[0088] On the other hand, when the panel pipe fitting temperature TP is determined as to
be 60°C or lower in step S33 (step S33: YES), or when the indoor heat exchanger temperature
Te is determined as to be 60°C or lower in step S34 (step S34: YES), occurrence of
a defect in the indoor motor-operated valve 23 is detected (step S35).
[0089] When occurrence of a defect in the indoor motor-operated valve 23 is detected in
the defect detecting process, for example, the occurrence of a defect is reported
to the user by means of indication on the emission display section 49 or the like.
<Features of Air Conditioner 1 of the Embodiment>
[0090] In the air conditioner 1 of the embodiment, the controller 7 has the defect detector
73 which detects occurrence of a defect in the indoor motor-operated valve 23 which
is configured to switch over between a state where the refrigerant flows in the panel
pipe fitting 36 of the radiation panel 30 and a state where the refrigerant does not
flow in the panel pipe fitting 36 of the radiation panel 30. Therefore, it is possible
to detect occurrence of a defect in the indoor motor-operated valve 23 by the defect
detector 73. This restrains dew condensation on the radiation panel 30 during the
cooling operation, and a defect in the surface temperature of the radiation panel
30 during the indoor motor-operated valve 23 during the warm-air heating operation
and radiation heating operation, which are attributed to the defect in the indoor
motor-operated valve 23.
[0091] Further, in the air conditioner 1 of the embodiment, the refrigerant circuit 10 has:
the principal channel 11 in which the outdoor motor-operated valve 64, the outdoor
heat exchanger 62, and the compressor 60 are provided in this order; the first channel
12 having the indoor heat exchanger 20, which, during the heating operation, connects
the branching section 10a provided on the downstream side of the compressor 60 in
the principal channel 11 with the merging section 10b provided on the upstream side
of the outdoor motor-operated valve 64; and a second channel 13 having the radiation
panel 30, which connects the branching section 10a and the merging section 10b in
parallel with the first channel 12. The indoor motor-operated valve 23 is provided
between the radiation panel 30 and the merging section 10b in the refrigerant circuit
10. Therefore, it is possible to detect occurrence of a defect in the indoor motor-operated
valve 23 in the air conditioner 1 in which the first channel 12 having the indoor
heat exchanger 20 and the second channel 13 having the radiation panel 30 are connected
in parallel with each other.
[0092] Further, in the air conditioner 1 of the embodiment, the defect detector 73 detects
occurrence of a defect in the indoor motor-operated valve 23, based on the panel pipe
fitting temperature TP detected by the panel outgoing temperature sensor 26 between
the radiator 35 of the radiation panel 30 and the indoor motor-operated valve 23,
and the indoor heat exchanger temperature Te detected by the indoor heat exchanger
temperature sensor 27 provided to the indoor heat exchanger 20. Therefore, it is possible
to detect the open/close state of the indoor motor-operated valve 23 by comparing
the panel pipe fitting temperature TP with the indoor heat exchanger temperature Te.
Thus, it is possible to detect occurrence of a defect in the valve structure, if the
refrigerant flows out of the indoor motor-operated valve 23 although the indoor motor-operated
valve 23 is supposed to be closed, or if the indoor motor-operated valve 23 is closed
although it is supposed to be opened.
[0093] Further, in an air conditioner 1 of the embodiment during the cooling operation,
the defect detector 73 detects occurrence of a defect in the indoor motor-operated
valve 23 only when the difference between the indoor temperature Ta detected by the
indoor temperature sensor 24 and the indoor heat exchanger temperature Te is 5 deg.
or greater. Excluding the cases where the difference between the indoor temperature
Ta and the indoor heat exchanger temperature Te is small, misdetection of a defect
in the indoor motor-operated valve 23 is restrained.
[0094] The embodiment of the present invention is described above with reference to the
drawings. However, it should be understood that the specific configuration is not
limited to the embodiment. It is noted that the scope of the present invention is
determined by not the description of the embodiment but claims of the present invention,
and that all meanings equivalent to the claims and all modifications within the scope
are included in the present invention.
[0095] The above described embodiment deals with a case in which the refrigerant circuit
10 that connects the indoor unit 2 and the outdoor unit 6 to each other includes the
second channel 13 that is connected in parallel with the first channel 12 in which
the indoor heat exchanger 20 is provided, and the radiation panel 30 is provided in
the second channel 13. Alternatively, the indoor heat exchanger 20 and the radiation
panel 30 may be connected in series with each other.
[0096] As illustrated in FIG. 12, a refrigerant circuit 110 of an air conditioner 101 according
to a modification of the embodiment includes a circular principal channel 111 in which
the outdoor motor-operated valve 64, the outdoor heat exchanger 62, the compressor
60, the radiation panel 30, and the indoor heat exchanger 20 are connected in this
order. The discharge-side pipe fitting and intake-side pipe fitting of the compressor
60 are connected to the four-way valve 61. Branching sections 101a and 101b are respectively
provided on both sides of the radiation panel 30, and both ends of a branching channel
112 are connected to the branching sections 101a and 101b. The branching section 101a
is located between the indoor heat exchanger 20 and the radiation panel 30, and the
branching section 101b is located on the opposite side to the branching section 101a
with respect to the radiation panel 30. Further, the branching section 101a is provided
with a three-way valve 123.
[0097] Between the branching section 101b and the radiator 35 of the radiation panel 30
is a panel incoming temperature sensor 25. Between the branching section 101a and
the radiator 35 of the radiation panel 30 is a panel outgoing temperature sensor 26.
[0098] In the refrigerant circuit 110, the four-way valve 61 is switched to a state indicated
by a broken line in FIG. 12 during the cooling operation. Further, the three-way valve
123 is switched to a state in which the refrigerant from the indoor heat exchanger
20 flows in the branching channel 112 but not in the radiation panel 30. Therefore,
as indicated by a broken-line arrow in FIG. 12, the high-temperature, high-pressure
refrigerant discharged from the compressor 60 flows in the outdoor heat exchanger
62 through the four-way valve 61. The refrigerant condensed by the outdoor heat exchanger
62 flows in the indoor heat exchanger 20 after being decompressed by the outdoor motor-operated
valve 64. The refrigerant vaporized by the indoor heat exchanger 20 flows in the compressor
60 through the branching channel 112, four-way valve 61, and accumulator 65.
[0099] During the warm-air heating operation, the four-way valve 61 is switched to a state
indicated by a solid line in FIG. 12. Further, the three-way valve 123 is switched
to a state in which the refrigerant ejected from the compressor 60 flows in the branching
channel 112 but not in the radiation panel 30. Therefore, the high-temperature, high-pressure
refrigerant discharged from the compressor 60 flows into the indoor heat exchanger
20, through the four-way valve 61 and the branching channel 112, as shown by the solid-line
arrow in FIG. 12. The refrigerant condensed by the indoor heat exchanger 20 flows
in the outdoor heat exchanger 62 after being decompressed by the outdoor motor-operated
valve 64. The refrigerant vaporized by the outdoor heat exchanger 62 flows in the
compressor 60 through the four-way valve 61 and accumulator 65.
[0100] During the radiation heating operation, the four-way valve 61 is switched to the
state indicated by a solid line in FIG. 12. Further, the three-way valve 123 is switched
to a state in which the refrigerant discharged from the compressor 60 flows in the
radiation panel 30 and in the branching channel 112. Therefore, the high-temperature,
high-pressure refrigerant discharged from the compressor 60 flows into the radiation
panel 30 through the four-way valve 61, and then flows into the indoor heat exchanger
20, as shown by the bold-line arrow in FIG. 12. The refrigerant condensed by the radiation
panel 30 and indoor heat exchanger 20 flows in the outdoor heat exchanger 62 after
being decompressed by the outdoor motor-operated valve 64. The refrigerant vaporized
by the outdoor heat exchanger 62 flows in the compressor 60 through the four-way valve
61 and accumulator 65.
[0101] In the air conditioner 101 of the modification too, the defect detector 73 of the
controller 7 detects occurrence of a defect in the three-way valve 123 configured
to switch over between a state where the refrigerant flows in the panel pipe fitting
36 of the radiation panel 30 and a state where the refrigerant does not flow in the
panel pipe fitting 36 of the radiation panel 30, as in the case of the embodiment
described above.
[0102] In the above modification, the outdoor motor-operated valve 64, the outdoor heat
exchanger 62, the compressor 60, the radiation panel 30, and the indoor heat exchanger
20 are connected in this order in the annular principal channel 111 of the refrigerant
circuit 110; however, the present invention is not limited to this. That is, the positions
of the radiation panel 30 and the indoor heat exchanger 20 may be other way around;
i.e., the outdoor motor-operated valve 64, the outdoor heat exchanger 62, the compressor
60, the indoor heat exchanger 20, and the radiation panel 30 may be connected in this
order. In this case too, the both ends of the branching channel 112 are connected
to the branching sections provided to both ends of the radiation panel 30.0 Further,
the three-way valve 123 configured to switch over between a state where the refrigerant
flows in the panel pipe fitting 36 of the radiation panel 30 and a state where the
refrigerant does not flow in the panel pipe fitting 36 of the radiation panel 30 may
be provided to the branching section positioned on the opposite side of the indoor
heat exchanger 20 over the radiation panel 30.
[0103] Further, in the embodiment described above, the indoor motor-operated valve 23 is
provided between the radiation panel 30 and the merging section 10b in the refrigerant
circuit 10; however, the present invention is not limited to this. For example, the
three-way valve may be provided to the merging section 10b, and this three-way valve
may be used as the indoor motor-operated valve 23.
[0104] Further, in the embodiment described above, the defect detector 73 detects occurrence
of a defect in the indoor motor-operated valve 23 based on the panel pipe fitting
temperature TP detected by the panel outgoing temperature sensor 26 provided between
the radiator 35 of the radiation panel 30 and the indoor motor-operated valve 23 and
the indoor heat exchanger temperature Te; however, the present invention is not limited
to this. That is, for example, it is possible to configure the defect detector 73
so as to detect occurrence of a defect in the indoor motor-operated valve 23 based
on the temperature detected by the panel incoming temperature sensor 25 provided on
the opposite side to the indoor motor-operated valve 23 over the radiator 35 of the
radiation panel 30 and the indoor heat exchanger temperature Te.
[0105] Additionally, in the embodiment described above, the defect detector 73 during the
cooling operation detects occurrence of a defect in the indoor motor-operated valve
23, when the difference between the indoor temperature Ta and the indoor heat exchanger
temperature Te is a predetermined value or greater; however, the present invention
is not limited to this. Misdetection is prevented by having the defect detector 73
detect a defect in the indoor motor-operated valve 23 when the pressure (low pressure)
in the indoor heat exchanger 20 is at a predetermined value or lower. Therefore, it
is possible to configure the defect detector 73 so as to detect occurrence of a defect
in the indoor motor-operated valve 23, when the difference between the indoor temperature
Ta and the panel pipe fitting temperature TP is a predetermined difference or greater.
[0106] Further, in the embodiment described above, the defect detector 73 during the radiation
heating operation detects occurrence of a defect in the indoor motor-operated valve
23 when the indoor motor-operated valve 23 is completely closed; however, the present
invention is not limited to this. That is, occurrence of a defect in the indoor motor-operated
valve 23 may be detected, not only in cases where the indoor motor-operated valve
23 is completely closed, but also in cases where the opening degree of the indoor
motor-operated valve 23 falls short of a required opening degree (an opening degree
to cause the surface temperature of the radiation panel 30 to fall within a panel
target temperature range).
[0107] Further, in the embodiment described above, occurrence of a defect in the indoor
motor-operated valve 23 is detected when (Formula 1) to (Formula 4) are all satisfied
during the cooling operation, when (Formula 5) to (Formula 7) are all satisfied during
the warm-air heating operation, and when (Formula 8) to (Formula 10) are all satisfied
during the radiation heating operation; however, the present invention is not limited
to this. That is, occurrence of a defect in the indoor motor-operated valve 23 may
be detected when at least (Formula 1) is satisfied during the cooling operation, when
at least (Formula 5) is satisfied during the warm-air heating operation, and when
at least (Formula 8) is satisfied during the radiation heating operation. Further,
numerical values given in (Formula 1) to (Formula 8) are no more than examples, and
are variable as needed.
Industrial Applicability
[0108] The present invention allows detection of a defect in a valve structure.
Reference Signs List
[0109]
1 Air Conditioner
2 Indoor Unit
6 Outdoor Unit
10 Refrigerant Circuit
10a Branching Section
10b Merging Section
11 Principal Channel
12 First Channel
13 Second Channel
20 Indoor Heat Exchanger
21 Indoor Fan
23 Indoor Motor-Operated Valve (Valve Structure)
24 Indoor Temperature Sensor
26 Panel Outgoing Temperature Sensor (Panel Temperature Sensor)
27 Indoor Heat Exchanger Temperature Sensor
30 Radiation Panel
35 Radiator
60 Compressor
62 Outdoor Heat Exchanger
64 Outdoor Motor-Operated Valve (Decompression Structure)
73 Defect Detector (Defect Detector)
123 Three-Way Valve (Valve Structure)