Thermo Products ome-72d36 Troubleshooting Flowchart, Note Check diagnostic code through view port

Models: ome-72d36

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TROUBLESHOOTING FLOWCHART

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

TROUBLESHOOTING FLOWCHART

Note: Check diagnostic code through view port

Set thermostat subbase to "HEAT"prior to removing doors. Does thermostat make contact?

 

 

No

 

 

 

 

 

 

 

 

 

 

 

Is room temperature

 

Yes

 

 

Wait for room air to cool.

 

above 90 deg. F?

 

 

 

 

Yes

No

Yes

 

Is room temperature above

Turn thermostat setting

thermostat setting?

 

above room temp.

No

Replace thermostat

Does a "call for heat" initiate an ignition cycle?

Yes

No

Is the power switch "off"?

No

Is there 120 VAC

across lines L1 & L2?

Yes

 

Yes

 

 

Turn power

 

 

 

 

switch "on".

No

Check input power. Reset circiut

 

breaker, or replace blown fuse in

 

disconnected switch.

 

 

Is the oil primary control receiving 120 VAC?

Yes

No

Have either of the

Yes

 

high limit thermostats

 

 

activated?

 

No

With power on,measure voltage across the aux. high limit thermostat N.C. contact to L2. If not 120 VAC, replace aux. high limit thermostat. Else,replace high limit thermostat.

Wait for furnace to cool. Look for cause(s) of high limit activation,eg. low airflow, over-firing, blocked flue,etc.. Correct any

abnormal conditions.

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Thermo Products ome-72d36 service manual Troubleshooting Flowchart, Note Check diagnostic code through view port