Troubleshooter - Maxitrol

Gas, air and flue

Check:

Gas supply
Check whether the pilot light gets smaller/weaker when the main burner (or any other gas-consuming device) ignites. If this is the case, the burner pressure is too low.

Combustion air supply
If the flames dance (unevenly) on the burner, this may indicate a lack of combustion air.

Check the following:
- Is the flue system permissible?
- Has the correct gable/roof pass-through been used (DRU brand)?
- - Does the gable/roof pass-through discharge into the prescribed areas (free from any interference from walls and roofs)?
- Are there any blockages?
- Is the appliance and flue correctly adjusted (air inlet guide, restriction slide, throttling ring)?

More information on the above can be found in the manual.

Pilot light burner
Is the pilot light too weak (dirty)? And does igniting the main burner pull it away from the thermocouple? 
If so, clean it with compressed air. Follow these instructions.