I've finished my diesel heater install and tried it out today. Ran it for about 2hrs, it had no problem keeping the trailer at +17C while it was +2C outside, and this is with no insulation.
I decided to mount the heater in the exterior case to keep both fuel and combustion outside the living quarters. This should be the safer option (vs. mounting the heater inside), and it's a pretty clean end result.
This is a 2kw, Vevor-branded Chinese diesel heater mounted in a plastic hard-case. I've added a 60mm 12v fan on the intake side of things to push fresh air to the combustion air intake, and I will (later) add another, identical fan on the opposite side to keep air moving, and to also suck out any potential exhaust leaks.
Everything is bolted together with stainless hardware, and all exterior-protruding hardware is sealed with sillicone. I opened up the heater and bolted the case to those L-brackets before assembling it all back together. Pushing on the heater shakes the entire trailer; it's as solid as it gets.
Top: air intake (this is the air that gets heated and sent into the trailer.)
Bottom: 12v fan, sucking fresh air in for combustion purposes.
At some point I will add overhanging "covers" for both openings, to prevent rain water intrusion.
- Power distribution bars (to neatly power the heater and fans).
- Exhaust covered in exhaust wrap and sent into a "through-hull" fitting.
- Diesel tank's movements are prevented by the two, metal L-brackets, and it's further strapped down by those two ski straps.
- Fuel pump mounted at the correct (30-35 degree) angle.
- Wiring neatly tucked away.
I used 2" sewer ducting and fittings to route hot air into the trailer. Great fit for the 60mm heater output, and easy to source at all local stores. I initially wanted to use metal fittings, but it then occurred to me that the heater casing is plastic, as are the fittings it comes with, so there shouldn't be any risk of any plastic melting. No issues in the few hours I ran the heater at max power, so I don't anticipate any issues down the line, either.
I'm waiting for a new exhaust hose to arrive, and will pair it with a muffler for the final install. The exterior exhaust will also be physically secured to the plastic case.
My only regret is running all three wires (power, ground, controller) separately. Laying in bed after making this install it occurred to me that it would have been better to use some 3/4" liquid-tight electrical conduit and to run all three wires inside it in one go. Oh well, live and learn.
The inside has this fitting, which is threaded for that same 2" sewer pipe. I can easily route this output to wherever I want. This (rear) interior wall will be getting framed out, insulated, etc., so this fitting will not be visible.