EC903 or Error Code 903
An error code 903 indicates a combustion abnormality, similar to an Error Code 90 but specifically related to the units ability to pull in combustion air or remove exhaust.
Common checkpoints:
- Check air inlet for blockage or obstruction.
- Check exhaust for blockage or obstruction.
- Check the Fan Motor. (ex. Clogging of fan blades, etc.)
- Check for sudden environmental changes. (ex. Hurricane, Storm, etc.)
If all of those items are normal the unit may need a fan motor adjustment, contact customer care for additional details. An external remote control will be needed to make a fan motor adjustment.
For further technical assistance call 866-766-7489 or use our Contractor Locator to find a local service representative.