Furnace problems

I think I'm a bit confused here. On my Montana High Country 5er I have multiple things available.

1. Heat pump on the front air conditoner, has it's own thermostat
2. Furnace, on the same themostat as #1 above
3. Second air conditioner (only) in the back on it's own thermostat
4. Electric heated fire place (stand alone)

How it all works together:

The 2 air conditioners are ducked through the roof and ducked together. Both air air conditioners can be run at the same time and both will blow air when running alone through the entire 5er. And the front one can be on heat pump while the back one is on air conditioning. (This has actually happened a few times).

When the front thermostat is flipped to heat (the front thermostat shows the current inside temperature at that thermostat. Next it has Auto, fan low, and fan high. Next step is select air conditioning or heat.

If selecting air conditioning, the air blows out the vents in the ceiling, through the entire camper. If selecting heat, the air conditioner turns off and the furnace turns on.

The furnace is ducked under the floor and runs the entire length of the camper. It's positioned forward of center, so the rear last vent is the longest run.

Also, the furnace ducks run under the floor and are open to heat the underbelly, and about 50% of the heat goes under the floor and about 50% in the living area.

Meanwhile, it's possible to have the furnace running (fan only-low or high, auto - low or high)

But the front air conditioner / heat pump and furnace don't run at the same time.

Again, furnace is under the floor. Air conditioning through the roof.

So the question is: Is yours hooked up the same way? (all air conditioning in the roof, and all heat under the floor?) if so, then it sounds like one of your heat ducks came loose in the underbelly.

Our 5er has 2 AC units and one furnace. It also has one Dometic thermostat that operates two zones or areas in the trailer. Zone one is the bedroom. Zone two is the living area. To set the thermostat, step one is to select the zone, then select AC, furnace, fan only, fan speed or off. Then set the desired temperature. Zone two is the living area. Use same technique to set thermostat.

We should be able to set zone two to furnace only and heat should come out of appropriate vents in the living area. What actually happens is heat comes out of vents in bedroom and bathroom, but NONE comes out of the vents in the living area. And the AC unit in the living area comes on, which should not happen.

It’s nit going to work the way you think it will.. if Zone 1 or zone 2 is turned in the air will blow out of ALL overhead ducts

If furnace is turned on air will blow out if ALL floor ducts

If furnace is turned on for Zone 1 and air conditioner is turned on for Zone 2 the heat will blow out of all floor ducts and cool air will blow out of overhead ducts..

Two different issues- set the front thermostat fan to “Auto” to keep the air conditioner blower from running.
As far as heat output, that’s a ducting issue, just need to inspect it to find the problem.

Thanks guys, all is well now.