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Error code reference
Carrier HVAC Error Code 36
Heater output not sensed when energized: fan coil control energizes either heater stage and does not detect the 24-Vac signal on output.
SourceCarrier Fan Coil Units - Service Manual: FB/FE/FF/FH/FV/FX/FZ/PF Seriesp. 15
Diagnostic procedure
The full 36 procedure
Step 1 is visible so you can confirm you are on the right page. The remaining steps, the ones that tell you whether to actually replace a part, unlock with any pass.
MyPros+ · DiagnosticsStep 1 preview
1
First diagnostic step
Check for 24Vac on heater stage outputs. Fan coil control or sensing circuit may be bad.
SourceCarrier Fan Coil Units - Service Manual: FB/FE/FF/FH/FV/FX/FZ/PF Seriesp. 15
More steps, wiring diagram references, and verified part numbers
Includes expected resistance and voltage values, connector pinouts, and supersession notes for replacement parts.
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