So I've got about 10 run hours on my all-in-one Chinese diesel heater now, and it's working out pretty well for me (running on 1K undyed pump kerosene). I've found TONS of information online about these, so I won't rehash their well known issues (critical pump mounting angles, exhaust drainage, yes, I have a CO detector AND meter, etc.), but here's what I added specifically to mine:
1) Kill switch - the internal control board to these units will continue to run forever until it receives a stop command from the control panel, and these electronic control panels are anything but reliable, and you must not simply pull the power from the heater, because they require a running fan for safe shutdown. So, should my control panel fail while in use, there's no easy way to safely shut the unit down. So, I mounted a toggle switch on the rear of the unit, in series with the fuel pump's power. Turn it off, and fuel delivery stops. My unit will throw an error 04 (fuel pump failure), and shut itself down safely, easy as pie.
I wouldn't consider using ANY of these heaters, whether it be Espar, Webasto, Chinese no-name, etc. without either a simple switch to stop the fuel pump or at least a fuel cutoff valve, and I don't understand why all of them leave this so simple feature out.
2)
Tilt switch - every modern kerosene heater I've used has one of these (even my Monitor heater, which isn't exactly something you can easily knock over), but the Espar and Webasto heaters are engineered to be bolted down (and the Chinese heater modules themselves are exact clones), so they don't need one, yet these Chinese all-in-one heaters are, well "Chinese engineered", so they're lacking this essential safety consideration once you ******** a tank and chassis and make the machine portable. I bolted the switch inside to the rear, and also wired it in series with my fuel pump. Which means it will also go into a safety shutdown (with the associated fan assisted cool-down). The bonus here is that if the heater is quickly re-righted after being tipped, the error 04 will lock out re-lighting until you manually intervene. A simple alternative to a tilt switch could be a momentary switch placed so that it is pressed only when the unit is firmly on a flat surface. I've got an electric space heater that uses one of these, but it means that you can't use it elevated on blocks.
3) Co-axial exhaust. Ok, here I go way overboard, but hey, why not. My 20kBTU Monitor heater already uses one of these, and it just makes sense to heat your combustion inlet air with your exhaust waste heat. Besides, a cooler exhaust is safer. I used a 15" brass "wall bend tube" from a 1-1/2" drain, but I had to shorten it, so a 12" tube would be fine.
I drilled this for the exhaust to run inside, and sealed it up with JB Weld (plain silicone seals the intake). The JB Weld burned up quite a bit, smelling pretty bad in the process, and I'm going to be replacing it with a better high temperature epoxy, but otherwise it works great (the exhaust tube is contiguous, so I know for certain that all exhaust is piped out, and if the inlet leaks a little, that's ok). A few screws near the far end of the brass tube keep the stainless flexible exhaust tube centered nicely, and with the brass trimmed to match the length of the stainless, the muffler shoved into the stainless provides just enough separation between inlet and exhaust. The thin stainless corrugated exhaust tube makes an ideal heat transfer surface. I really couldn't have picked something better. The far end of the brass is always cold, 2" behind the heater where it passes the door is cool enough to touch, and by the time I get to the rear foot, it's quite warm.
I mentioned this co-axial exhaust elsewhere, and someone commented that the warm intake air would throw off the mixture. Well, one thing I've noticed is that this unit has an automatic altitude compensation, and while I am at sea level, it showed an altitude near 0m when I bench tested it with just direct exhaust, but now shows that I am near 100m with the coaxial exhaust, so whatever these do to automatically compensate for "altitude" must be optimizing combustion pretty intelligently. I wonder if they're using an oxygen sensor in the combustion chamber...
The last picture shows it venting through an exhaust port in my garage door. The 6" opening makes it easy for me to pass the exhaust tube with the muffler installed right through it, and a bracket on the door mates with a part I attached to the foot on the rear of the heater to keep it stably in place.
Is this anywhere near as nice as my Monitor heater? No. It's quite a bit louder, though also much smaller and the output is similar. The biggest issue is that the Monitor will gracefully shutdown if it loses power unattended, whereas this will likely melt it's internal electronics if it loses power and I don't supply air to cool the combustion chamber quickly.
