Cranky

Thanks. I had found the first one with an internet search. Coincidentally, same way I found this forum. The other two will be helpful also. Thanks again.

I have not tried connecting the blue wires directly to the thermostat. Only when I plug in the 4 pin harness plug between the coach and the furnace. I will give this a shot when I get back to it. I just meant that the blower will run even if the gas does not ignite.

Didn't flip the plug, it does have two D shaped receptacles to prevent the accidental of plugging it in backwards. Mine is old enough that it does not have an on/off switch on the furnace. Wish it was that easy, lol. Couldn't find any rubbing, pretty sure at this point that the motor bearings are going and maybe an imbalance on the squirrel cage fans is contributing to the noise. The old give it a smack on the side would quiet it down for awhile. But the noise always comes back.

Hi, I have an older RV with a SF-25 furnace in it. It has outside access and is pretty easy to remove. The furnace was working fine, but making a lot of noise/whining when running. So I pulled it out to see if I could lube up any moving parts and to make sure nothing was rubbing. When I put the furnace back in place, it will now not turn on. I have good voltage all the way to the time delay switch. But not going from the time delay switch to the motor. When I jumper the two blue wires on the furnace, I can get it to come on. But it will shut off shortly after removing the jumper. It does not have a no spark shut off and will run without ignition. The 4 wire connection from the rv to the furnace has 3 purple wires and one green(ground). I have good voltage (13V) coming from the one purple wire that matches up to the red on the furnace. Should there ever be voltage from either of the other two purple wires that match up to the blue wires on the furnace harness. What went bad on me from pulling it out and putting it back in? What other troubleshooting should I do? Thanks for your time and input.