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Discussion Starter #1
I have a 2000 camp trailer and used it a couple weekends ago and went to turn the heater on and the fan kicks on but it wont kick on the fire. Just wanted to get some ideas if maybe its something simple to check before i take it in to have it looked at. I have checked all the simple stuff, has gas fuses are all good. Not sure if its in the heater itself or the switch controls on the wall.
 

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check the thermocouple probe.
 

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Discussion Starter #3
Where about would this be? whats it look like? thanks
 

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in your more modern trailer, it bprobably comes from a "control module'. it is a small diameter copper tube with a 'bulb' on the end.
This end is positioned directly over( or at end of) flame tip. The function is to cause the gas supply to be interrupted or shut off if/when the flame goes out.When igniting, the control module will supply gas to the pilot light until the flame is steady or enough heat to allow the thermocouple to open for full gas supply.
If this thermocouple is faulty, the full gas supply will not allow gas to fire up the burner.
poor explanation, but hope you get the gist of it.
thermocouple costs around $14.00-$50.00.
 

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I had a 1986 trailer with a gas heater that had a circuit board in it. I had the same type malfunction with mine, circuit board was fried. Then it happened a 2nd time. Wasn't cheap either. If thermocoupler in yours is ok, look to see if there is a module/circuit board.
 

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Discussion Starter #7
WEll got to talking with one of the mechanics at the trailer shop and found out i have a bad thermstat, the one that hangs on the wall. I can hook the wires direct bypassing the thermostat and she will fire right up. So gonna pick one up in the morning and get ready for camping this weekend. Thanks for all the replys guys.

Thanks again

Jeremiah
 

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Don't believe your thermostat is bad. The fan would not have started if it was. The fan starts and blows for about 10 to 20 seconds to purge any gas (leakage) in the combustion chamber so it won't explode on regular ignition. If you have'nt had the propane turned on for some time, it may take 5 or 6 tries to get the air out of the system. Most all furnaces after 1997 have 3 try electronic boards in them. The best way to purge the air out of the system is to light the stove if you have had the propane shut off for a couple of days or more. What make furnace do you have ( Suburban - Atwood Hydroflame ) Does your thermostat control both the furnace and Air conditioning. All RV DSI (direct spark ignition) furnaces operate this way. Thermostat calls for heat -- fan turns on for purge cycle-- purge timer times out--(if the sail switch is made) gas valve opens & spark ignition fires--if ignition does not occure within 5 seconds gas valve shuts off--there is no thermocouple on this type furnaces, only a flame sensing rod that gets red hot. If the furnace requires you to light a pilot, then it will have a thermocouple and still go thru a similar cycle, if it did not light fire off, this type, If your 12VDC is low (10.5VDC) the fan is not running fast enough to make the sail switch, then no ignition will occure on either type furnace. On a furnace with a 3-try board it will go thru 3 cycles with 10-15 seconds between ignition for purging, fan will continue to run until thermostat is turned off, then back on to repeat the cycles. Listen for a click (gas valve opening) if not heard then the valve is stuck,defective or the board is defective, assuming the sail switch is made.

OLDBULL /ubbthreads/images/graemlins/smokin.gif /ubbthreads/images/graemlins/smokin.gif /ubbthreads/images/graemlins/rolleyes.gif
 

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Discussion Starter #9
Well with the thermostat connected the fan will run but will not ignite. I completely removed the thermostat and hooked the wires direct for my heater and just as you say the fan will start then moments later it will ignite and work just fine. I disconnect the wires and the fire will go out but fan will stay running untill cool enough to shut down. This is what leads me to believe its the thermostat.


What you did describe is exactly the style of furnace i have. I had run low on batteries one time and the fan would run but would not ignite.

Furnance is a Suburban, and yes the thermostat controls the AC and furnance.
 
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