furnace " clicking " noise

[Jamesadixon48]

On our last camping trip, we heard a clicking noise coming from the outside of our trailer. I traced it to the side of our unit where the furnace vents to the outside. Not only was it clicking, but it also was trying to blow air out the vent. I checked the thermostat inside and made sure the mode for furnace was off. The temp outside was in the 90's and both air conditioners were running, so there was no need for the furnace to even try to be igniting. When nothing I tried on the thermostat made the noise stop, I decided to open the vent compartment where the noise was to see if I could see what was clicking. As I was about to undo the last screw from the vent, the noise stopped and didn't come back. I don't know what happened, but I have to get it in to the dealer. Any ideas?

[egregg57]

The clicking noise may have been your igniter trying to light the furnace. It will click several times to light the burner. If on the first attempt the burner does not light, there will be a pause and the furnace will attempt to light again. It will do this three times before it stops attempting to light. Failure to light off can be a blockage in the tubing, or more often propane not getting to the igniter.

Was your thermostat on auto? If so, it is possible that the furnace temperature was set to a temperature close to the AC set point, lets say 70 degrees. On AUTO there is a minimum differential needed between the furnace set point and the AC set point. Consult the Dometic Thermostat woners manual. My wife isn't very "technical" she turns something on and expects it to do what she wants. Not unreasonable in her book...

However, when the AC is set to 70 degrees, the furnace is set to 70 degres and the Fantastic fans are also set to about that temp... The AC is running full blast, the furnace is also running and the vents are.. well...venting!

So IF this was your circumstance, setting the AC to 72, furnace to 68, and vents to about 76 is enough differential to have things work properly.

Of course you may already know all this stuff and I am not really helping! i don't know!

Eric

[jcurtis934]

Using the program modes or using auto mode is asking for issues. Want ac, use "cool" mode for one or both ac's. Want heat, use "furnance" mode. The only auto I use is for fan speed. The thermostat really is a simple, easy to use device...unless you try to mess with its mind and...then it is going to bite you. John

[stengels]

John is correct, if yu have both zones set in AC mode, the furnace won't try to come on. We run this way from Spring to Fall unless a chilly spell is predicted. We can then change the zone for the furnace so that it comes on.

[1retired06]

quote:Originally posted by jcurtis934

Using the program modes or using auto mode is asking for issues. Want ac, use "cool" mode for one or both ac's. Want heat, use "furnance" mode. The only auto I use is for fan speed. The thermostat really is a simple, easy to use device...unless you try to mess with its mind and...then it is going to bite you. John

X2!