Technical Articles

FAQ - What does a 90 error code mean?

A 90 error code indicates a combustion abnormality.  This means that the mixture of fuel and air is off from specification and is resulting in poor quality combustion. 

Common issues associated with a 90 error code:

1) Insufficient gas supply
2) Blockage in the flue vent
3) Debris in the fan motor

It is recommended you contact a servicer to troubleshoot this error. 

Please visit to find a local service representative.

Applicable Models
  • Models: ALL MODELS
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