2020 fuzion 419 furnace issue

[mgrote]

Been having to run the furnace here in Iowa lately at night, it's been running fine until last week. Here's the problem, the fan comes on and runs, the fire won't light to make heat so the fan shuts off after about 30 seconds of running. Is the spark to light the fire bad or what could be the issue? Also, how does one even access the furnace for repair or cleaning on a 2020 Fuzion 419 floorplan?

[flybouy]

Originally Posted by mgrote

Been having to run the furnace here in Iowa lately at night, it's been running fine until last week. Here's the problem, the fan comes on and runs, the fire won't light to make heat so the fan shuts off after about 30 seconds of running. Is the spark to light the fire bad or what could be the issue? Also, how does one even access the furnace for repair or cleaning on a 2020 Fuzion 419 floorplan?

Some more details would help. Do you have propane? Do you hear a "cliking" sound when the furnace first comes on? When the furnace failed last week did it coincide with anything else like changing the propane tank?

[mgrote]

Originally Posted by flybouy

Some more details would help. Do you have propane? Do you hear a "cliking" sound when the furnace first comes on? When the furnace failed last week did it coincide with anything else like changing the propane tank?

Yes, I use propane and yes the tanks are /12 to 3/4's full. I don't hear the clicking sound when it starts up that's why I'm wondering if the spark ignitor is bad. Ours doesn't have the option to switch to electric heat either it only runs with gas. Everything is controlled by the in-command system.

[JRTJH]

Based on the sequence of operation, I'd look first at the sail switch/burner chamber purge function. If, when the fan starts turning, it doesn't develop enough air velocity to close the sail switch, then the "clicking will not occur"...

My guess would be either a faulty sail switch (a problematic issue for many trailers this past winter), low DC voltage (fan can't turn at full speed) or a dirty furnace fan (can't move enough air because of dust, pet hair, etc caught in the fan "squirrel cage").

[sourdough]

As another potential problem; this trailer, on its maiden voyage (close to home), after it had worked fine on PDI, started doing exactly what yours is doing. Took it in and they replaced the control board on the spot. No problems since. Just another "potential" problem to consider.

[Fuzion1278]

The above posts are all potential problems as stated. Since the blower is starting and runnning for a while then shutting down, my first guess would be the "cheap" sail switch supplied by the manufacturer. I had an entire season of sail switch problems, 2 of them going bad so I fixed the problem myself, (in the heating and air business all my career). I paid a technician to pull the furnace out as it was a nighmare to get to, (wires and plumbing all in the way). I then repaired it and paid to have it reinstalled. Second season the cheap 15 amp breaker mounted on the side of the furnace went bad and was intermittantly tripping, without the presence of high amps or any shorted wires. I removed it from the circuit myself because the circuit is protected by an external 15 amp fuse as well. This season was finally trouble free. Just had it on all last weekend during cool nights with no issues.....finally.

[manonfire1978]

It's the sail switch, had the same thing happen to my 2019. dealer will warranty it.
They told me that a bunch had faulty ones installed but have since been upgraded, blows me away that they recognize the problem but don't issue a recall.