Cotton Wood Pass, CO
DIY Diesel Heater
We originally started this trip off with only having a small Mr Heater Little Buddy to keep us warm in the roof top tent. The Little Buddy uses Coleman style 1lb propane tanks and seemed like a good idea at the time due to its size and portability. However we soon found it it lacked in several areas:
-Under 5hrs of run time
-Lots of condensation produced
-Easily knocked over
-No temperature setting
-Cost of fuel adds up fast
-Can't keep up in extream temps
Our ground tent accommodations while repairing the truck in Fairbanks Alaska.
The heater worked out alright but for the above reasons we hardly used it. The worst downside was the condensation. In a small roof top tent we would wake up to having the walls and ceiling dripping wet. Not something you want to deal with while camping. However the real deal breaker was when we were in Fairbanks Alaska. Long story short, we had to repair the wheel bearings of the truck and live in a ground tent for the 2+ weeks it took to get all the parts and make the repair. As you can imagine it gets very cold in Fairbanks and snow was in the forcast. Thankfully our hosts had a brand new diesel heater they hadn't installed in their camper yet and were gracious enough to give it sell it to us.
An animated image showing how a diesel heater works
Heater Tool Box Installation
I'd never heard of a diesel heater or as some people call them parking heaters before this moment. They're actually quite simple in design. You have a small diesel engine surrounded by a plastic case that takes in outside air using a fan, runs the air over the hot diesel engine and blows that air out the other side. The small engine has it's own intake and exhaust ports to ensure you don't get harmful carbon dioxide in your sleeping area. Originally these heaters were over $1000 to purchase but over the last few years there have been Chinese manufactures making much more affordable heaters. You can find heaters now for under $200.
Brand new diesel heater ready to install.
You can find these Chinese Diesel Heaters on both amazon and eBay for a fraction of the cost of the name brand heaters. Here is the heater we installed from Amazon. The whole kit comes with just about everything you need to get going. More on that later. The main unit has an intake and exhaust manifold along with a small fuel port that pokes out the bottom of the heater. A metal plate is provided that sandwiches the heater to a flat surface and also allows for safe heat dissipation near the exhaust port.
Heater installed in tool box
I chose to mount the heater inside a weather sealed tool box. This is the Dewalt Tool Box "Tough System" (DWST08203). Has really robust plastic construction with a rubber seal that surrounds the lid of the box great for keeping water out. A simple rectangle was cut out of the plastic and bolts holes to run the bolts to secure the heater inside the box. The whole heater "floats" inside the tool box as it's secured to the front side of the tool box.
Next was to drill the holes for the outside air inlet and the hot air output. The kit comes with an air inlet that worked great. For the hot air output I found these neat sort of quick connect fittings (Deflecto EZDock) so you can take the hose that connects the heater to the roof top tent quickly.
Then the fuel pump and filter needed to be installed. The included fuel filter is terrible and almost leaked instantly. I'd suggest using something like this one. The fuel pump is next in line and comes with a rubber noise isolator that has a hole to mount it. I have it mounted under the heater out of the way. Unfortunately the noise isolator doesn't help too much with the clicking of the pump. It's something I'd like figure out in the future as you can hear the pump from the tent.
Testing out the heater in the ground tent.
Heater testing time. In a ridiculous turn of events it actually started to snow as we started to turn the heater on. Good timing to say the least. The first initial reaction was WOW! The volume of air this heater produces is incredible. It takes about 4-5 minuets to get the heater warmed up to the hottest temperature. I let the heater run all day for about 6hrs and nothing caught on fire. Yay!
Mounting to the Rear Bumper
So the heater should be easily accessible and always ready to be set up quickly. To do this the most obvious choice was to mount it to the rear bumper. Without the tools to make a real mount I chose to strap it to the jerry cans. I hope in the near future I can weld up a proper mount but on top of the fuel cans worked out pretty well. It also put it in a great position to be close to the roof top tent and a power source. While ratchet strapping it to the jerry cans was easy finding a place for the fuel tank would require some work.
Sizing up the tank to be mounted to the jerry can holder between the propane tank. Tracing some lines from the jerry can holder I was able to line up the preexisting holes on the tank to mount it. A simple metal bracket bridged the gap on part of the gas can holder that didn't have as much material.
To help keep the black and grey aesthetic of the truck I used some black Flex Seal our hosts had laying around to paint the tank. I used a bit of tape to mask off a line so we could see the level of fuel remaining in the tank. I later marked a line at each gallon filled to help us keep track of fuel consumption (not shown). I had to make two more small brackets to stand off the propane tank holder.
Hard to see in the above pictures but you'll notice the 6 nuts and bolts holding the relocated propane tank. Everything mounted up and looking good. Really filled out the swing arm. It's really nice having so much utility everywhere on the truck.
Here it is all set up. We didn't have the time or the resources to make a proper bracket for the heater box but the ratchet strap has held up great until we get the opportunity to improve it. Not ideal but it actually works great other than having to access the jerry cans. In the meantime it keeps us warm and makes for a really easy and quick setup. Everything fits inside the box until it's needed. Simply connect the exhaust pipe and dryer hose and plug in the power and we're all set.
Using a dryer hose has worked out great. They are affordable, heat resistant and fold down to a compact size that fits inside the heater box. Along with using the Deflecto EZDock connection I haven't found anything that might work out better but it would be nice to have a one that was black in color to be less obvious.
Duct running into roof top tent and thermostat
Using the heater is really simple. First you open up the box and connect the power cable. I have a DC cigarette outlet right inside the camper shell. Then I connect the short exhaust pipe and make sure it's not near anything as it gets very hot. Next is to connect the dryer duct to the heater and poke the other end into the roof top then. Finally I throw up the thermostat into the roof top tent and climb up. The whole set up process takes maybe 2 minutes tops.
Thermostat display changing over the 5 minute start up process.
To start the heater you simply press the power button on the thermostat for about 2 seconds and the heater goes though it's starting process. In the first minute the glow plug warms up and the display shows a red glow plug. After a minute you hear the fuel pump turn on and start clicking slowly and the display shows a blue fuel pump logo. You also notice at this time the graph that shows the internal temp. After 2 minutes you can usually hear the roar of the fire inside the engine. At just about 4-5 minutes it's up to temperature and blowing very warm air and you should see all 6 bars of full heat indicated.
Cycling though the OK button information screens.
The heater can be either controlled by setting a temperature or setting a frequency. I tried the temperature setting at first but it would turn the heater on and off constantly so setting the frequency as worked out best. The value is between 1.2Hz and 5Hz. In such a small space like the roof top tent I can normally have it set to 1.2 to 1.6Hz and be very comfortable in most conditions. The coldest I have camped at was -8F and had the heater set to 2Hz.
So far in even -8F the roof top tent stays a nice 75F! That's only using less than half the capacity of the heater. I really hope I can return to Alaska and go find some -30F camping and see what this bad boy can do.
Energy and Fuel Consumption
Power Consumption Graphs
To test the power consumption of the heater I used my Victron BMV-712 Battery Monitor to create some graphs. One thing to note is that with everything off in the truck there still seems to be a small 7 watt ghost draw. So subtract 7w from the graph to get accurate numbers. Also the heater is set to 1.6Hz of continuous heat.
You'll see in the graphs the heater uses just over 100 watts in the first minute. I want to guess this is the glow plug warming up. This only lasts a minute then drops down to about 18 watts with a little moment where it hits just about 40w but this small jump only lasts about 2 minutes where it stops at about 12 watts. I want to guess this is the heater finding the frequency I set manually at 1.6Hz. This is usually the highest setting we use so I thought it would be a good setting to test. So at the highest heat setting you would need for a roof top tent the heater uses 12 watts of power. That's 18Ah of battery power for every 24hr of continuous heater use. See the above gallery for the power consumption for other power levels.
Now obviously with outside air temperature and how comfortable at night you like to be changing per person and situation I found it very easy to have the heater set to the lowest setting for most nights. I also found the outside air temperature had little effect on the heaters capability. Even at our lowest camping temperature we only needed to set it to 2.0Hz and took the same time to heat up (5 mins). I'd also like to note that I've used this heater all the way up to 11,000ft in elevation with zero issues. Really impressive.
Finally the heater does a great job using little fuel to keep running. At the 1.6Hz setting the heater uses a little less than 1 gallon of diesel per 24hrs. With the 2.6 gallon (10L) tank you could use this heater for about 5 to 7 days before needing to top off the tank depending on how many hours you need the heat.
Snow camping with the diesel heater
Final Thoughts After 6+ Months
This has been one of the best if not necessary upgrades that the truck has recieved. There's no way I'll ever go camping in low temperatures without one again that's for sure. From the subzero temperature of Alaska to the altitudes of Colorado this little cheap heater hasn't let us down. That's also after hanging off the rear bumper for at least 10000 miles now in snow, rain, dust and so many bumpy roads. The reliability of this heater was really the most surprising. For a cheap Chinese knockoff it's definitely preformed over my expectations.
We stopped in Telluride Colorado for a few months and rented an apartment to make some money before moving on. The heater sat on the bumper unused for 4 to 5 months in some extreme temperatures (-10F to 70F). Before leaving Telluride I went to go start it up to see how it was doing. The heater started right up without any issue. I can't recommend them enough.
In fact a friend of ours who has a very large motor home installed one recently and they claim even at it's lowest setting they have to leave a window open or they get way to hot. Incredible.
If you're looking for a reliable heater at a very good deal I would highly recommend a Chinese Diesel Heater. Please feel free to email me if you have any questions or want to share any stories from your installation.
Camping with the heater at 11000ft and 6F.