Airwell EDS25 Service Manual page 55

12.3.6.2 Handling the thermistor faults in a COMP unit
i. ICT/OCT thermistor is disconnected or shorted -
The invalid thermistor temperature is replaced by 43
can continue the normal operation. All protections related to that faulty
thermistor will be disabled. For example, in case of any ICT fault, the ICT
high pressure protection in Heat Mode and ICT defrost protection in Cool
Mode will not operate anymore. The same is also applied to the OCT fault.
ii. RAT thermistor is disconnected or shorted –
The RAT will be derived from the ICT by using the equations :
Notes:
In case of any thermistor failure, the STBY LED will be blinking until the
fault condition is corrected.
the thermistor faults.
i. RAT thermistor is disconnected or shorted –
System will operate continuously in the last IFAN & WVL status when
turned ON.
Notes:
As in the COMP unit, the STBY LED will be blinking to indicate a
thermistor fault. And, the user can use the system diagnostics function
Service Manual - EDS
Heat Mode: RAT=ICT/2.3
Cool Mode RAT=ICT*4
Revision
o
c, so that the unit
0
CONTROL SYSTEM
12-5