Suburban Furnace has 2 Amp Phantom Load when off

[Andy-RV1]

Folks,
Just took a trip in my fifth wheel. 2003 Cougar with suburban furnace. It had been off the road for about 20 months so I checked out all the subsystems.
AC, Fridge, Furnace, Water Pump, Hot Water Heater all seemed to work fine.
My generator is not working so I was dry camping.
Found that I could not get through my second night without a low battery setting off the CO/Propane detector. That will wake you up!
Was able to run the tow vehicle intermittently to keep things running, but clearly had some unexpected power usage.
Back home I was able to identify that the furnace circuit is drawing 2 amps with the thermostat in the off position.
So my current assumption is that there is some short in the furnace or some circuit is energized which should not be.

Anyone experience anything similar on a suburban furnace? It is an SF model, I think the SF30F, but I am not sure.

I pulled the furnace fuse for now, so I dont have that drain, but would like to track done the issue.

Has anyone experienced anything similar?

Any help is appreciated.
Thanks
Andy

[Fisherman]

Lwiddis wrote:
“My generator is not working so I was dry camping.”

Generators are not considered a “hookup.” Consider solar.

And what does your solar have to do with his furnace situation, absolutely nothing.

[Old-Biscuit]

DC is always AT the furnace
Comes from the FUSED Source (DC Dist Panel) to the furnace controls
Furnace controls would be either a 'Timed Delay Relay' OR 'PWR' circuit on the circuit board (model/vintage dependent)
DC also goes to the Thermostat

2A Draw is high when not running

Find/ID the Source Fuse and see IF it is being used for something else then just furnace

Furnace motor can draw 8 - 11.5 Amps (Model dependent)
But only when running

See Pgs 34 - 36 for wiring diagrams

Suburban RV Furnaces

[Edd505]

GO to iRV2 and message old biscuit, he's an expert in RV electric.

[BFL13]

Is there another circuit on the same fuse as the furnace? Follow the wires. Or does something else not work too that is easy to spot that might be worth 2 amps? Single DC light on in a compartment you seldom open?

[time2roll]

I would be following the current with my DC clamp-on ammeter. Make sure that power is actually getting just to the furnace and then see what is warm in the unit.

[Lwiddis]

“My generator is not working so I was dry camping.”

Generators are not considered a “hookup.” Consider solar.

[dougrainer]

Is it a RVP or Dometic tstat? Is the furnace controlled by the same Tstat as the roof AC? Or, do you have an aftermarket wall tstat that is programmable. A 2 amp draw on a GOOD fully charged battery will not drain overnight. Doug

[Andy-RV1]

Even when they are OFF? I mean like the thermostat is set to OFF, the temp is set to very cold. The only draw should be the thermostat it self. Hmmm. Now thats a thought. I will check that next.

[Dusty_R]

Most gas furnaces will drain the battery in one night or less.

Dusty