Furnace blower doesn’t work

[Mimiof4]

Our 2019 Forest river Wildcat furnace stopped working .It only blows cold air. Help.

[007matman]

Propane?

Does the stove light?

[Mimiof4]

Yes it’s propane. And the stove does light. It had been working fine and just stopped.

[007matman]

Try turning the system off for a bit.

Otherwise, maybe someone else will chime in. Sorry.

[Mimiof4]

Thank you for any input. I really appreciate anything

[Mimiof4]

We did that too. Could it be a fuse

[TimVWulp]

are you plugged in to 110 volts power? need full 12 volts to run furnace it is a power hog and will drain your battery fast.

did you turn furnace off and back on to reset furnace control board? may need to do this several times if you have air in the propane lines.

Have all 3 stove burner lit and on high when you start the furnace to rule out propane regulator or hose. if burners go out or goes low you have a propane system problem.

Below is a link from the library at the top of this page in the green bar. It is a very good trouble shooting manual for suburban furnaces. The trouble shooting section starts around page 23 of the manual.

Make sure you do the three burner stove test when you try to start the furnace as this will eliminate any problems with the propane system.

There have been a lot of problems with the suburban control boards failing. If you find the control board has failed replace it with a dinosaur brand control board. This brand is a much better made control board for the furnace, refrigerator, hot water heater than the ones that came with the appliance.

Forest River Forums - Downloads - Furnace - Suburban Operation (Various models)

Hope this helps Tim

[Mimiof4]

Thank you

[Rich5117]

When you say only blows cold air. Does the furnace continue to stay on and blow cold air or does it shut off after a few minutes?When it attempts to start do you hear any clicking by the igniter? Also if you go outside near the furnace vent do you smell any propane or feel heat being vented?

The furnace has a start up sequence. It will start the blower to assure proper air movement, after several other checks it will open the gas valve that is when you should hear clicking, the furnace will try this 3 times then if it fails will go into lockout. After that it will not attempt to start.

[nayther]

Originally Posted by Rich5117

When you say only blows cold air. Does the furnace continue to stay on and blow cold air or does it shut off after a few minutes?When it attempts to start do you hear any clicking by the igniter? Also if you go outside near the furnace vent do you smell any propane or feel heat being vented?

The furnace has a start up sequence. It will start the blower to assure proper air movement, after several other checks it will open the gas valve that is when you should hear clicking, the furnace will try this 3 times then if it fails will go into lockout. After that it will not attempt to start.

concur. The first thing that happens is the blower comes on and closes the sail switch, proving air is moving in the combustion chamber. If sail switch does not close it locks out the burner, hence the reset. Once air flow is proved the burner will try to light, that's the "clicking" mentioned, you may have to go outside and listen at the heater. It sparks/clicks for a few seconds and if the flame proving switch (thermocouple) does not sense a flame it shuts off and goes through the sequence again. If flame comes on you will hear the roar and you will have heat. The burner stays on until thermostat is satisfied and then the sequence is reversed, flame goes out but blower stays on until firebox cools down. Also if you open up the outside cover you'll see the circuit board, there's a blinking LED that can be "read" and the error code checked.



Common problems are low air flow causing high limit trip or blockage in the burner tube from insect nests. I've had to disassemble one and clean out the actual LP jet from a spider web.

[5picker]

Originally Posted by nayther

concur. The first thing that happens is the blower comes on and closes the sail switch, proving air is moving in the combustion chamber. If sail switch does not close it locks out the burner, hence the reset. Once air flow is proved the burner will try to light, that's the "clicking" mentioned, you may have to go outside and listen at the heater. It sparks/clicks for a few seconds and if the flame proving switch (thermocouple) does not sense a flame it shuts off and goes through the sequence again. If flame comes on you will hear the roar and you will have heat. The burner stays on until thermostat is satisfied and then the sequence is reversed, flame goes out but blower stays on until firebox cools down. Also if you open up the outside cover you'll see the circuit board, there's a blinking LED that can be "read" and the error code checked.



Common problems are low air flow causing high limit trip or blockage in the burner tube from insect nests. I've had to disassemble one and clean out the actual LP jet from a spider web.

Nice write up but wanted to mention/add, some furnaces have no outside cover that can be removed. Mine doesn't, it looks like this on the outside... this is all you see...

[nayther]

Originally Posted by 5picker

Nice write up but wanted to mention/add, some furnaces have no outside cover that can be removed. Mine doesn't, it looks like this on the outside... this is all you see...

Not had a trailer without the large panel on the exterior but there's got to be access to the furnace inside then for service.

[nayther]

Originally Posted by nayther

Not had a trailer without the large panel on the exterior but there's got to be access to the furnace inside then for service.

to add to this I didn't realize I have the same combustion vent setup as shown. I removed the interior R/A grille and there's nothing to be found there either, just the backside of the furnace. I'm going to have to poke around more to find the circuit board. I'll do that when I get to modifying the return air to quite it down, hate listening to the blower.

[dcheatwood]

On my 4th RV and never had outside furnace access. Only fridge and water heater. Furnace has always been behind a wood panel inside somewhere.

Originally Posted by nayther

Not had a trailer without the large panel on the exterior but there's got to be access to the furnace inside then for service.

[boondocking]

I had the same problem a few years ago and it turned out to be the gas valve.
The furnace would start and blow cold air until I gave the gas valve a whack with a wrench. Then it would work properly until the next call for heat cycle.
I replaced the gas valve and it worked just fine after that.