Travis of YetiAmbo talks about running a webasto coolant heater for his unit and a 12 volt compressor for the AC here:
Seems like that is a better option than tossing the factory stuff and replacing with roof mounted units..
Since my 2009 Crestline is the New Era (which is smaller module) I thought the heat & AC just ran from the cab. But on taking panels off today I discovered not only more unused storage space but also a small Heating and AC unit.
In playing with the thermostat it seems that it is both Heat & AC but neither work with the engine off.
I've been googling around trying to find more info on it but to no avail.
Would be great if someone has a link to the documentation or some insight from their own modification.
Was showing the rig off to a buddy this afternoon. Weather is bloody cold for May so it was a good heater test.
The rear heater (as expected) works from the engine coolant. So, connecting a 12 volt coolant heater into it all will work. Will it be as efficient as a Webasto Airtop? No idea... but it would be multipurpose in that it could also heat up the shower water, etc plus make for easy starts on during the cold Canadian winters.
Rear AC also worked with the engine running, this seems to indicate the rear unit does not have it's own dedicated compressor.
Now, what I know about HVAC systems is practically nothing but wouldn't something like one of these 12 volt mini-AC compressors work?
There are fairly low BTU but ... since the box is insulated it seems that one could use the engine driven compressor to get the temps down to reasonable and then switch to the low draw 12 volt system to keep the temps tolerable?