(57) A safety device for gas heating apparatus, is provided which is responsive to a reduction
in the oxygen content in the environment in which the apparatus is located, to close
a main solenoid valve (3) controlling the gas supply.
The device includes a temperature transducer the temperature sensitive element (13)
of which is fixed to the outside of the wall (16) of a pilot burner tube (2) to detect
its temperature. In dependence on the detected temperature, the transducer generates
a signal which, when the pilot flame burns in a first position (A) in the pilot burner
tube (2), corresponding to normal environmental conditions, maintains the gas-supply
solenoid valve (5) open and which on the other hand causes the latterto close when
the pilot flame burns in a second position (B) as a result of its displacement due
to a lowering of the oxygen content in the environment.
|
|
