| (19) |
 |
|
(11) |
EP 0 345 098 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
12.12.1990 Bulletin 1990/50 |
| (43) |
Date of publication A2: |
|
06.12.1989 Bulletin 1989/49 |
| (22) |
Date of filing: 01.06.1989 |
|
| (51) |
International Patent Classification (IPC)4: F25B 47/00 |
|
| (84) |
Designated Contracting States: |
|
DE ES FR GB IT SE |
| (30) |
Priority: |
02.06.1988 GB 8813051
|
| (71) |
Applicant: HUSSMANN MANUFACTURING LIMITED |
|
Glasgow, G5 OXZ
Scotland (GB) |
|
| (72) |
Inventor: |
|
- Gardner, Derrick, Edward
Nr Loughborough
Leicestershire LE12 6LB (GB)
|
| (74) |
Representative: MacDougall, Donald Carmichael et al |
|
Cruikshank & Fairweather
19 Royal Exchange Square
Glasgow G1 3AE, Scotland
Glasgow G1 3AE, Scotland (GB) |
|
| |
|
| (54) |
Refrigeration system |
(57) A defrost monitor (24) comprises a thermistor probe (26) located adjacent to the
evaporator (14) of a refrigeration system (10) which is connected to a programmable
controller (28) located within the monitor (24) to which is connected a second thermistor
probe (30) for detecting temperature rises above a preset value entered into the controller
(28) and during defrost of the refrigeration system (10) the programmable controller
(28) assesses the rate of change of temperature between given preset values and if
the rate of change indicates defrost will activate a valve (22A) and heater (32) thereby
assisting defrost or initiate an alarm or the like where the rate of change is irregular
or the temperature remains between the two preset values thereby indicating a refrigeration
fault.