It probably wouldn’t be that hard to add a vent. I have thought about an auxiliary with a fill, but haven’t climbed under to look. There are some smaller ones I hoped would fit a space somewhere.
My biggest problem is, it’s not that cold where I am and have slept fine down to 25º with just a sleeping bag and blanket. The small one mounted through the bed is really nice though. I would never put an all in one with an exhaust connection inside the space, that’s a big no no, but might just do a leave it outside all in one.
Here is what I went with. I just added a hanger onto my tire swing out to hold the heater when it’s being used. For now I will just transport it inside the truck. Unfortunately my old spare tire spot already has an air tank and compressor. I wanted to keep everything off the ground. I still need my exhaust pipe extension and to clean up the wiring on the truck side.
Running the duct to the upstairs. Fuel is in the tire backpack. I need to clean up my wires and get an extension for the display unit. I still might tap into my main tank but it’s not really worth the hassle considering I don’t need the heater too often.
Here is the fuel and wire pass through and air intake with removable silencer. @keeganbuilds had the links to some nice power plugs and 3” adapters that I used. Everything seals up and fits into the case for transport.
Here is the homemade sheet metal adapter for the horse trailer dust vent. This clips on and runs heat into the bottom section. It also draws some ambient air through the outer vents.
I would recommend buying a quality muffler. Look at the difference between the stock unit and this autoterm unit. The stock muffler is not even baffled. Night and day difference. Between the muffler, intake and all the insulation it’s almost silent when running.
This is the one I went with. They are somewhat local to me. Kinda pricey when it’s almost half the cost of the heater! At least you get some nice sturdy clamps!
It can go either way. I found unless it’s super cold it works best to heat the downstairs only, it creates a heated mattress effect and is quite comfortable. Piping the air in to the tent section aways ends up too hot for us.
As far as the hose trailer vent. The main benefit is how well it keeps the dust out of the GFC but using it for ventilation and heating is an added bonus. When they are facing into the wind when driving they pull in tons of air and create a positive pressure in the GFC.
My heater in a case is still undergoing to modification and testing but I will do a complete write up when I’m satisfied with everything.
Cheap Chinese one with a super easy setup. I throw it in the black bin in the background of the first photo and slide it in the back when not in use. Sets up / breaks down in under five minutes and high enough to be out of the snow. Second photo I forgot the tire table but shows the vent routing. Nice and toasty down in the single digits.
