Coleman Presidential II burns 30 secs, then goes out

[Guest]

I have a Coleman Pres II that is driving me nuts. I have replaced the thermocouple, the gas valve and still the same symptoms. The pilot lights great and burns continuously. The thermostat is calling for heat and the burner lights just fine, then in about 30-45 seconds the burner and pilot go out. It is an LP system and the kitchen stove works fine on the LP so I don't think it's the LP system.

I have disconnected the limit switches and the system still either does the same thing or won't light. What else could it be??

D Hicks

[Robert]

Hi,

What is your model number ? Will be back on later tonight.


Thanks,
Robert

[Guest]

Sorry I didn't put the number... 7655-856. It was working and then it sat for some time, this is at the lake house. I noticed that it has a time delay relay MARS MS 106 1A 45 75C, could this be the culprit?

Thanks
D Hicks

[Robert]

Hi Delbert,

Is the blower motor running when they go out ?

What does the burner flame look like when it's burning ?

What color is it ?

Have you checked the flue and roof-jack for damage and/or blockage ?

Thanks,
Robert

[Guest]

The blower is not running when it goes out. The burner is burning full and solid, it is blue with red tips. I have not checked the roof jack. The house has a metal awning coving it and the jack comes up through it. I have been up there, but have not removed the cap. I have has a leak there when it rains. The water puddles on top of the heater itself or runs down the side. I have been up there caulking up the leak, but this happened before that.

[Robert]

Hi,

When working correctly, what was the normal time delay from time burner ignites until blower motor kicks on ?

If the blower does not kick in soon enough, could go out due to overheating, but that involves the Limits.

Other possibility is lack of oxygen and combustion process smothering itself out.

This is something that is hard to determine without being there with proper tools to test the cycle and see what is/isn't happening.


Take care and best wishes,
Robert

[Guest]

The normal time delay was around 1 minute. After the burner lights it continues to burn for about 30-45 seconds, then it goes out. It does look like it is starved for air because the pilot goes out too. I adjusted the air by sliding open the air port on the burner assembly, but it made no difference. I know for certain that the vent is clear.

[Robert]

Hi,

Time to call a Tech and have the unit cyle tested to determine problem.

The normal DIY type things have been covered and the only way to find what is wrong is by testing for proper operation specs.

Guessing any further would be a costly measure when it may be a minor repair.

Take care and best wishes,
Robert

[tlv]

We had issues with our heater a few months ago with the pilot light staying lit. It was the regulator on the propane tank. It didn't have anything to do with the heater itself. You may want to check that out. We have the people that fill our tank also service it.

Good luck