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Error code reference
Lennox HVAC Error Code 204
The air-handler's blower motor will not start.
SourceLennox CBX40UHV - Service Manual: Installation & Service (HFC-410A)p. 35
Diagnostic procedure
The full 204 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 seized bearing, stuck wheel, or obstruction. Replace motor or wheel if assembly does not operate or meet performance standards. The system will go into watchguard mode.
SourceLennox CBX40UHV - Service Manual: Installation & Service (HFC-410A)p. 35
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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Where this code is documented
1 manual in the MyPros+ library documents this code for Lennox hvac.
Models covered by the manuals that document this code
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