I recently picked up a Propex HS2211 heater from Karl at Westy Ventures; here are a few pictures and some details in case anyone is considering a Propex.
This unit can be mounted inside or outside (I'm planning on outside mounting for several reasons, including keeping all of the propane outside and for reducing noise; I'm a really light sleeper)
The heater can also be mounted in additional orientations compared to the HS2000 and HS2800 which are older models. This unit appears to have an updated thermostat, although the other models may include this as well, or maybe not.....
When mounting inside, 3 holes need to be drilled through the van: Combustion intake air, exhaust air, and propane line.
For outside mounting, 3 holes also need to be drilled, two rather large holes for the hot air and cold air return duct, and the wiring harness to the thermostat.
Duct Y fittings are also available as well as closable vents. If you are only running one hot air vent, it has to be fixed open. If two or more hot air vents are installed, at least one has to be fixed/open.
The wiring harness connects the heater to the thernostat and to a 12V supply. It has a nice rubber bootie for the heater side for outside mounting.
The supplied propane inlet fitting is a 5/16" compression fitting for copper (or steel/stainless) tubing. I picked up a compression to male NPT brass adapter in the event that I want to run a hose to the unit instead of rigid tubing. For inside mounting, rigid tubing is highly recommended.
The thermostat can be flush mounted with the supplied trim, or surface mounted with the supplied PVC spacer. The knobs have cool white o-rings, we'll see how long they last......
I also ordered grommets for the ducting since I'm planning on outside mounting; they are very low durometer rubber. Hopefully I'll be able to find a flat surface under the floor for the duct holes since they won't work too well in the corrugated parts of the van floor.
The ducting and vents screw into the white coupler. It appears that the max panel thickness for the vent mounting is at least 3/4". Two fixed vents, two white couplers and about 4' of ducting are supplied in the kit. The duct appears to be cardboard fiber material with a metallized ID.
I've already got lots of ideas for mounting, perhaps a sub-frame, rubber isolator feet, a weather cover, etc.