** Help ** Mid-trip Fan Problem

smkinseattle · 09-08-2018, 09:52 PM

Hi, we are mid-trip in the northern Canada. We have been using our Heat with no problems at all (AC once ok as well). I have run into a problem very recently where the Fan just blows cool air (via the heating vents) and will not stop ever. I have checked my panel ... even with the HVAC "off", it still runs. If I turn the heat on with valid temp ranges, it does nothing. The only way to shut it off is to unplug and shut the override off in the front storage - it continues to run and runs against my battery, even when towing. This is a a huge problem until I get back to the Seattle area to get to a dealer - BTW our unit is a 2019 Keystone Cougar 24SABWE.

Any help would be really appreciated!
Thanks!
-Scott

KeithInUpstateNY · 09-08-2018, 09:56 PM

It doesn't solve the underlying problem, but pulling the 12V fuse for the furnace should stop the fan from running and draining your battery.

smkinseattle · 09-08-2018, 10:00 PM

Thank you - I will look again at the panel - I didn't see anything clearly marked for the furnace or HVAC. In the "master panel" looks like a bunch of fuse "modules" versus what I am used to seeing ... any suggestion on what to look for?

KeithInUpstateNY · 09-08-2018, 10:09 PM

Your panel has two sections, usually the 120V breakers like you have at home are on the left, the 12V fuses are on the right, different colors for different amperages. The furnace fuse should be a blue 15. There should be a corresponding numbered list next to it. The furnace may be labeled "FUR" or "FURN". Count down from the top to find the number with the furnace label. You can pull it with needle nose pliers. If the fan doesn't shut off put it back in and try the one above or below it until you find the right one. Good luck!

KeithInUpstateNY · 09-08-2018, 10:38 PM

But I'm wondering if the problem isn't that you accidently turned the fan to the continuous on setting at the thermostat. If it is the square digital Dometic thermostat it's easy to change settings without intending to.

smkinseattle · 09-08-2018, 10:56 PM

Don't think that is the problem - I have the iN-Command panel. I have the mode set to "heat" source set to "gas" and fan set to "auto" ... even if I cycle the fan to "off" and mode to "off" ... this thing is still running. It is blowing cool air out of the external vent (that is usually red hot) and blowing cool air through the floor vents.

notanlines · 09-09-2018, 12:46 AM

I have no solution to your thermostat problem, but pull the fuse as directed and the furnace blower quits!

**JRTJH** · 09-09-2018, 06:19 AM

We're talking about an "emergency/on the road repair" not a troubleshooting and problem resolution repair. With the digital thermostat, mono-wire multiplexing thermostat connection to the Dometic control box in the rooftop A/C, in command control system and furnace electronics, it's not a "simple mechanical mercury thermostat switch" any longer. If you're not familiar with troubleshooting digital systems, you'd be better served to just pull the fuse, live with a small electric heater for the rest of the trip and let your dealer/service technician fix it permanently when you return home.

Attempting to "pull wires, troubleshoot systems, change out boxes and find a fix" may or may not solve the problem. It could be a software interface problem, a component problem, a loose plug or a malfunctioning component/components. It may even be a corroded electrical wire connection that's not allowing enough voltage through the connection.

If you're not familiar with the system, how it works and how to troubleshoot it, even if you do "get it to work right now" do you have any idea if it was your action that fixed it or was there an intermittent problem that "towing shook back into working order".....

Pull the fuse, finish your trip "with the inconvenience of no furnace" and get it fixed properly when you get home. If your "fiddling around" shorts out something and you burn up another component, you may wind up with a trailer that you can't use to finish your trip, until that "other part you messed up" is fixed. Typically when that happens, there's no spare parts in stock where you're stranded and your trip is ruined.

If it ain't a simple fix, just work around it until you get home by pulling the fuse and accommodate the loss of furnace with a space heater.

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