Dometic furnace won't come on - until I kick it ;)

[medic149]

My mother always said, "if it doesn't work, hit it". Well, it worked, but I am looking to fix it now.

My furnace wouldn't come one. After troubleshooting the thermostat, fuses, and more, I figured it must be the furnace.

Furnace would not click or anything. Tried reseting. Nothing. Then, I "lightly" kicked the furnace box and it came on! The motor seemed sluggish and it changes speed sometimes when I tap on the exterior of the metal furnace box.

So, any thoughts?? I'm thinking a loose wire or at the worst a crack board.
Does anyone know if you can gain access from the side the picture is taken from?

The way Jayco installed it, I can't get access to the backside at all.

Oh, and the tape and screening you see is there to reduce mice from getting in. Haven't had any, but my last camper they got inside the furnace. It doesn't impeed air flow at all.

Thanks,
AJ

[mini4mw]

Never know, but I'd check ground first. Seems to be a common thread with general electrical issues. Especially as many systems use common grounds and they get mucked, corroded, rusted, etc. Anyway, that's the first place I'd try hunting.

[TCNashville]

You may have a malfunctioning sail switch. Kicking it might reposition the switch to make it functional. Common problem and cheap and easy replacement.

[Tommyjay]

I take it that you mean the blower wouldnt come on until you kicked it?

Had a problem with my 'fine' dometic furnace this winter. The blower ran, but it wouldnt fire. I narrowed it down to either the sail switch, or circuit board. A tech that I hired before said the dometics had a problem with the sail switch, and that I should go outside, and rap on the access door to get the sail switch moving. I dont have an exterior access, so I rapped on the top from the inside, and it worked. I eventually had a new sail switch installed, and had no problems.

....until today. Its been sitting since the first part of April with the battery disconnected, and water drained. So I filled up the water tanks, re-connected the batteries (they checked at 12.42 volts), and went through my checks.

Water pump - good
Hot water tank - filled, and fired up for heating
Refer - fired up on propane
Furnace - nothing.

Checked the reset switch on the furnace - on (the thermostat wont work if its off)
Checked the fuse - good
Tried to cycle the blower only - I can hear a click from the thermostat, but nothing from the furnace.
Ran through the trouble shoot section, and Im at the 'call the tech!' step.

Ill try kicking, and see what that does, but dometic has become a four letter word in my vocab.

[Tommyjay]

Originally Posted by mini4mw

Never know, but I'd check ground first. Seems to be a common thread with general electrical issues. Especially as many systems use common grounds and they get mucked, corroded, rusted, etc. Anyway, that's the first place I'd try hunting.

Thanks, but where would the common grounds be generally located?