Dutchmen Furnace Issue

[djurden]

I have a 2011 Dutchmen RV. I am having a problem with the furnace. When I turn it on at the thermostat, the fan comes on fine. After a few seconds, I hear a clicking sound (I assume this is the furnace trying to light). Then about 1-2 minutes later the fan turns off. No warm air comes from the vents. I can get the fan to come back on by turning the heater off and back on at the thermostat. But it does the same thing. No warm air and the fan only blows for 1-2 minutes.

Is there anything I can do? Or do I need to take it to a repair shop. The closest is about 1 hour drive!

THANKS!

[sundancer 87]

Originally Posted by djurden

I have a 2011 Dutchmen RV. I am having a problem with the furnace. When I turn it on at the thermostat, the fan comes on fine. After a few seconds, I hear a clicking sound (I assume this is the furnace trying to light). Then about 1-2 minutes later the fan turns off. No warm air comes from the vents. I can get the fan to come back on by turning the heater off and back on at the thermostat. But it does the same thing. No warm air and the fan only blows for 1-2 minutes.

Is there anything I can do? Or do I need to take it to a repair shop. The closest is about 1 hour drive!

THANKS!

Sounds like it's a problem with LPG delivery. The ignition source is firing but no gas is being ignited so the system times out.
Check there is sufficient gas getting to the furnace's gas valve.

[djurden]

Do you have any suggestions on how to do this?

[sundancer 87]

Originally Posted by djurden

Do you have any suggestions on how to do this?

The place to start is with a full tank of gas of course. The stove and refrigerator will operate on low gas pressure but the furnace needs more for operation.
You may have an automatic switch over two stage regulator that has gone south. The flag may show green but not be flowing enough gas for the furnace. You probably don't have a manometer to check gas pressure at the furnace but you can build one or you can even connect a BBQ grill tank and regulator to the furnace.
You can get a single stage regulator almost anywhere to bypass the automatic one to see if that is the problem.

[sundancer 87]

This is generic description of RV furnace operation and applies to most DSI type furnaces.
1. The Thermostat calls for heat, sending DC current to the furnace.
2. A Time Delay Relay is energized and passes battery DC power to the blower motor.
3. The blower motor and fans spin, pulling air from the Air Return and generating a stream
of air through the Heat Exchanger and out the Ducts. At the same time another fan pulls
air from the Combustion Air Intake into the Combustion Chamber and out the Exhaust.
4. The fan air stream causes the Sail switch to close as the blower gets near full speed.
5. Power flows to the High Limit Switch and onward to the Control Circuit Board.
6. The Control Circuit Board opens the gas valve and generates a spark at the DSI Igniter.
7. The Burner ignites, building heat in the Combustion Chamber.
8. Heat passes through the Heat Exchanger, warming the air circulating through the Ducts.
9. The Thermostat reaches the Set Temperature and opens.
10. Power is removed from the Control Board and the Burner shuts down.
11. The fan continues to run to cool the furnace, until the Time Delay Relay opens again.
For a Pilot Light model of furnace, the operation is similar but ignition does not depend on a
control board to trigger an igniter. Once the pilot is lit (manually), it stays lit and is the ignition
source. The furnace cycles on/off by control of the gas flow alone, with the gas valve opening or
closing in response to the thermostat demand.
An RV furnace runs strictly on 12 volt power (12 VDC) and does not depend on shore power or
generator to operate. As long as the RV’s batteries have sufficient voltage and amps, and there is
a supply of propane to produce heat, the furnace will function.

[ewarnerusa]

Agreed on it sounding like a gas delivery issue. Usually you need to purge the lines first if you've just opened the regulator valve at the tank. Do this by turning on a stove burner and trying to get it to light. If you do not hear hissing of air/gas coming from the burner when you turn the dial, then gas line may be locked up (I don't the right term, vapor lock?). Go out side and close the regulator valve and open it again very slowly. Like 30 seconds for the first quarter turn. After that first quarter turn, I've found that you can just open it up the rest of the way normally without going slow. It's that first pressure release that must be done slowly.
Go back in and repeat the line purging task with the stove burner. Sometimes you can hear the hiss of gas/air coming out but it still won't light. Shut the stove burner off and back on and repeat until things light. I like to then fire up all three stovetop burners to really get the gas flowing. Shut that stuff back off and try the furnace again. Hopefully it will light. Sometimes this process has to be done in order to get the fridge to light its propane burner as well right after opening the regulator valve.
Another thing to check for is kinks in the fuel line to the furnace. Our furnace is under a couch that is not fixed to the camper floor. One time it slid away from the wall and when I pushed it back against the wall it kinked the fuel line between the couch and wall. Woke up to a freezing camper and wondered why. After cycling the thermostat off and on, the furnace was behaving as described in the OP. Furnace worked fine after removing the kink.

[djurden]

I got it working last night! Not sure what actually did it; I did several things:

1) Switched propane tanks. I turned it on slowly. I read that this helps with air in the line. The other propane tank is full. I had the burners on the stove burning with it. (I did not go back and test it with this tank)
2) Lit all burners on stove and lit pilot light in oven and turned it on.
3) Turned refrigerator to gas and on.
4) Opened the outside cover to heating unit and disconnected the plug to the control board and cleaned it by blowing compressed air. I also blew compressed air all around the compartment.

When I went back in and turned the thermostat on, the fan came on and a few minutes later HOT AIR!

[sundancer 87]

Originally Posted by djurden

I got it working last night! Not sure what actually did it; I did several things:

1) Switched propane tanks. I turned it on slowly. I read that this helps with air in the line. The other propane tank is full. I had the burners on the stove burning with it. (I did not go back and test it with this tank)
2) Lit all burners on stove and lit pilot light in oven and turned it on.
3) Turned refrigerator to gas and on.
4) Opened the outside cover to heating unit and disconnected the plug to the control board and cleaned it by blowing compressed air. I also blew compressed air all around the compartment.

When I went back in and turned the thermostat on, the fan came on and a few minutes later HOT AIR!

Good deal! Let's hope you cleared the problem.

[vincent.boyd]

Had that happen to mine. The dealer had to replace the igniter. Also thought it may have been the thermal coupler but it was the igniter.

[djurden]

Well...it was working...

Now when I turn it on, I can hear it ignite. It will stay that way for about 5 seconds, then go out. The fan continues to blow. A few seconds later it will ignite again for about 5 seconds and go out. It does this a few times, then the fan goes off. I turn the furnace off and back on at the thermostat and it does the same thing.

[sundancer 87]

Originally Posted by djurden

Well...it was working...

Now when I turn it on, I can hear it ignite. It will stay that way for about 5 seconds, then go out. The fan continues to blow. A few seconds later it will ignite again for about 5 seconds and go out. It does this a few times, then the fan goes off. I turn the furnace off and back on at the thermostat and it does the same thing.

Last week when the temps dropped to 10 degrees the house furnace wouldn't operate correctly. The system would go through the process of ignition only to create very low BTUs. It cleared after the sun came out and hasn't been a problem until this morning. Another 10 degree start of the day with the same problem until the temp rose to 15 and then the furnace starting working properly.
I determined the problem to be the regulator at the propane tank (1950 vintage). It wasn't a big concern so I put off replacing the regulator. As soon as the snow melts I'll go to the propane company and purchase a new regulator.
I believe moisture is in the regulator and it freezes not only from the cold temps but from the cold LPG passing through it.
Go get a new regulator man, it's a cheap place to start.

[drflash]

I don't know for sure, but I have had two problems with the furnace staying ignited. The First problem was a faulty regulator which did not let enough pressure (therefore gas) to reach the furnace. Once that was solved, we worked pretty good for about a year. The Next problem we had was oil in the lines. The RV repairman blamed the propane supplier who denied a problem. Anyway I disconnected the propane from the stove, hot water heater, furnace, and refrigerator. Then disconnected from the regulator, and blew compressed air through the lines. Closing all with one open. then switching to the next and so on. I retrieved about a pint of oil from the lines. Hooked everything back up and we are in business. The oil had no smell. Don't know where it came from, but I am good now. (The rv repairman wanted to remove and replace all the lines for about $2000)

[lcv800]

Great job. Love to see it when someone does a repair and saves big money. Weird about the oil. Almost worth it to have it tested to see what it was.
Rusty

[meterman]

Probably cutting oil for the hard line


Sent from a place I no not where

[drflash]

If it wasn't such a large amount I would have thought so, but if it was, the installer must have filled the pipe to cut it. Interesting