Furnace help

[wthebeau]

I just bought a 1989 excella. I’ve been trying to get the heater to fire up. The fan comes on and I have cycled through the light up instruction. Be heat! I upend the gas line to insure that there is gas to the heater, check. I checked the fuse, it’s good. There is no manual pilot to light.
Help

[Rocinante]

Check to see whether there’s a sail switch in your furnace, and if so, whether it’s working.

[wthebeau]

Is that the Valve that open and lets gas into the heat chamber?

[rmkrum]

That is a switch that senses proper airflow from the blower, when that switch closes, then the gas valve and ignition comes on.

[Rocinante]

Originally Posted by rmkrum

That is a switch that senses proper airflow from the blower, when that switch closes, then the gas valve and ignition comes on.

Exactly, and if that switch isn’t working properly, or if your blower isn’t moving enough air, no heat!

[SeeMore]

Depending on your level of knowledge, using YouTube may expand your ability to diagnose the issue. Try searching YouTube for "RV furnace sail switch" and viewing the clips.

[wthebeau]

Is it located under the cabinet with the blower or outside with the heater unit? One other question do you know if the blower recycles the air from inside or is it always pulling fresh air from the outside? My lower is located under the stone and has a removable panel to access. I have three air vents but don’t see a filter or return air duct.

[eubank]

Wayne, as a first step, locate the manufacturer and model of your heater. It should be on or near the lid.
Lynn

[Lumatic]

Originally Posted by wthebeau

Is that the Valve that open and lets gas into the heat chamber?

The sail switch is not a switch you can manually turn on/off. It is a mechanical/ electronic sensor located inside the furnace.

If the furnace in your excella is basically the same as my 93 it is a Hydroflame and would be fairly easy to remove for repair or replacement without disassembling your trailer to do so.

[Rocinante]

If you can access the furnace from the outside via the door behind which they are usually installed, this may be your best bet. A sail switch is a “ten dollar part.” The money comes from knowing where it is, how to test it and how to replace it...or so my dealer told me when ours failed. [emoji57]

[eubank]

What's kind of interesting is that the sail switch in our old NT30 furnace failed repeatedly. However, the last replacement that I bought had been redesigned with a slightly larger sail. No more failures.

Lynn

[wthebeau]

It was the sail switch. Fixed! Thanks all

[Rocinante]

Woot! Congratulations!

[donh1]

Did you have to remove the furnace

[eubank]

Varies by make and model. Our NT30 does require removal. I've worked on others that did not require it. Of interest, however, is that the NT30, even with removal, was the easier job.


Lynn

Originally Posted by donh1

Did you have to remove the furnace

[donh1]

Thank Eubank for your reply. Will check model number. Been to cold (2 degrees) in the Tn mountains to get much done. Thanks. My trailer is a 85 model

[eubank]

By make and model, I mean the make and model of the furnance, not of the Airstream. On older rigs, many have had appliances swapped out.
LYnn

Originally Posted by donh1

Thank Eubank for your reply. Will check model number. Been to cold (2 degrees) in the Tn mountains to get much done. Thanks. My trailer is a 85 model

[donh1]

My furnace is a NT 30 S sorry it took so long. After looking at it I think I will have to pull the furnace. Thanks for the help

[eubank]

Yep, on that model, the sail switch is accessible only from the back side of the furnace.

To remove, disconnect wiring and gas. Unscrew from the floor. Remove the screw from the outside vent. Pull it out.

I replaced the sail switch so often on ours that I finally bought some ultility trailer hitch wiring connector and used it as a quick connect for the furance's main wiring.




Lynn

Originally Posted by donh1

My furnace is a NT 30 S sorry it took so long. After looking at it I think I will have to pull the furnace. Thanks for the help

[donh1]

Thanks for the help Eubank
Where did you purchase the upgraded sail switch
Trailer wires was a great idea. Thanks again
DON