TROUBLESHOOTING GUIDE

All installations and services must be performed by qualified service personnel.

TROUBLESHOOTING GUIDE

THE SYSTEM IS STARTED BY SETTING THE THERMOSTAT TO CALL FOR

HEAT. THE FOLLOWING SHOULD HELP ESTABLISH THE TYPE OF MALFUNCTION OR DEVIATION FROM THE NORMAL OPERATION.

TO USE THIS DIAGRAM, YOU JUST NEED TO FOLLOW THE INSTRUCTIONS IN THE BOXES.

NOTE: CHECK DIAGNOSTIC CODE THROUGH VIEW PORT PRIOR TO REMOVING ACCESS DOOR.

TURN THERMOSTAT TO CALL FOR HEAT

 

DOES THERMOSTAT MAKE CONTACT?

No

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

No

 

 

 

 

No

 

 

 

IS ROOM TEMPERATURE

 

IS ROOM

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Yes

BELOW THERMOSTAT

 

 

TEMPERATURE

 

 

 

 

 

 

 

 

 

SETTING?

 

ABOVE 90 DEGREES F?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Yes

 

 

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TURN T'STAT

SETTING ABOVE

ROOM TEMP.

IS THE TRANSFORMER

SUPPLYING 24 VOLTS

TO THE THERMOSTAT?

Yes

REPLACE

THERMOSTAT

Yes

COOL THE THERMOSTAT

No

 

ARE WIRES CONNECTED

No

 

PROPERLY?

 

Yes

 

IS INTERNAL DAMAGE

No

 

PRESENT ON THE

 

TRANSFORMER?

 

Yes

REPLACE TRANSFORMER

CORRECT WIRE CONNECTIONS

CHECK INPUT POWER, DOOR INTERLOCK, SERVICE SWITCH AND FUSES.

IS THE INDUCER

BLOWER OPERATING?

Yes

No

IS THERE 24 VOLTS ACROSS "TH" & "TR"

AT THE INTEGRATED CONTROL MODEL?

Yes

No

CHECK FOR CONTINUITY

&PROPER CONNECTIONS

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Thermo Products CMA1-50N, CMA2-75N service manual Troubleshooting Guide