Van Build #5 – Heating and Cooling
by Koda
The first thing to consider when thinking about heating and cooling your van is whether or not you expect to travel in sub-freezing temperatures. You can save a lot of valuable interior space by installing fresh water, grey water (from the sink and shower) and black water (from the toilet) under the floor of the van. In most cases this also allows you to have larger tanks. The more fresh water you can carry the longer you can boondock without having to drive into town – if your grocery supply holds up. It seems obvious then that placing all your water tanks outside the living space is the way to go – unless the outside temp falls below freezing. Frozen pipes and tanks would be a disaster you definitely want to avoid. Water system design is covered in Van Build #4.
Heating
Using the engine to heat your van
There are various methods of heating the living space inside your van. The cheapest in terms of up front costs is to simply run the engine and use the standard vehicle heater. This quickly becomes expensive as you pay the price of fuel to run a large engine rather than just enough to create the heat alone. It also reduces the overall life of your engine.
It is impossible to heat the living area of the van with the engine if a solid wall separates the cab from the rest of the van. Separating the cab from the living area might seem like a good idea because it provides far more insulation from the outside heat and cold and makes the van more stealthy. One of the trade-offs is losing the ability to heat the living area with the van engine in case of emergency, such as running out of fuel for the gas or diesel heater, or having the heater break down. If you lose all your heat while in sub-freezing winter conditions it is not just uncomfortable, your water pipes and water heater could freeze and burst.
Electric space heaters
Another cheap up front but ultimately expensive heating method is using an electric space heater. $35 will buy a 1,500 watt electric heater with a fan which can keep a well insulated van comfortable on cool but perhaps not cold nights. To use one you would need at least a 2,000 watt power inverter – 3,000 watts if you also run other appliances at the same time, and roughly 600 watts of solar power and 600 amp hours of lithium battery storage. That will cost around $6,000 US and you need a huge van to put that many solar panels on the roof. Electric heat ends up being the most expensive and you can lose all your heat after 2 or 3 cloudy days in a row.
Propane Heaters
Small, stand alone propane heaters are inexpensive and can heat a small space well enough to be much more comfortable than having no heat at all. The downsides are always needing to replace the small gas cylinders, and the fact that they produce water vapor. The moisture collects on the inside of your windows and frequent use can cause mold and mildew to develop inside your walls. They work fine for an unexpected chilly evening now and then, but using your vehicle heater will avoid the moisture problem, while using a lot more fuel.
Gasoline and Diesel “Parking Heaters”
Most people end up installing gasoline or diesel “parking heaters”. (They are called parking heaters because they are intended to be used only when the vehicle is parked.) They often come with a 10 liter (2-1/2 gallon) fuel tank, which is enough for 2-7 nights, perhaps more, depending on how cold it gets outside. It is much more convenient to use the type of heater which matches the type of fuel in the main fuel tank of the vehicle so you tap into that. Some vehicle fuel tanks come with an auxiliary fuel line which you can tap into directly, while others require removing the fuel tank in order to modify the fuel gauge assembly. I read that newer Sprinters have readily accessible auxiliary fuel lines but the older ones do not, so I dropped my fuel tank only to see the auxiliary fuel line sitting right out in the open. Some vehicles may require drilling a hole in the main fuel tank. If this is the case, leave the bottom of the fuel line you install about 2 inches above the bottom of the tank. You don’t want to run out of fuel when you are in the middle of nowhere.
Diesel heaters operate by having a small fuel pump squirt tiny pulses of fuel onto a burner plate where the fuel is initially ignited with a glow plug. Once the heat inside the combustion chamber becomes hot enough the glow plug shuts off and the heater draws about 50 watts to run the pump and fan. The heater usually mounts to the floor and you need to use a carbide tipped hole saw to drill holes for the air intake and exhaust pipes to pass through. I imagine gasoline heaters work in much the same way as diesel heaters but use a spark plug rather than a glow plug.
If you plan to be stealthy so you can park on city streets in the winter, using a diesel heater will definitely blow your cover. The fuel pump makes a ticking sound like a loud clock and the exhaust sounds like a far away jet engine. Anyone walking past your van will know someone is inside because of those sounds.
The name brand diesel heaters cost a fortune, around $1,200, so many people, including myself, opt for the cheap Chinese version which you can get for under $200. The one drawback to the Chinese version is that the thermostat does not turn off the heater when it reaches the set temperature. The instructions are almost useless and changing settings sometimes requires pressing multiple buttons at once. You may not know which buttons to push till you spend enough time watching YouTube videos to learn how to use the controls. At less than one-fifth the price of a name brand heater a little inconvenience seems worth the savings. The manufacturer claims the heater will operate for 40 hours on 10 liters or 2-1/2 gallons of fuel, and that seems to be true on low settings
My diesel heater has stopped working 3 times in 4 months. I thought the problem was caused by running the heater almost non-stop for several weeks at the lowest heat setting, resulting in soot build-up inside the combustion chamber, but it might also be caused by high winds preventing the exhaust from getting out properly. The problem begins with seeing clouds of white smoke when I first turn the heater on. (I later discovered that the smoke caused the entire undercarriage of my van to become covered with black soot.) After looking at a bunch of poorly made YouTube videos I discovered that the easiest fix is to use an electric air pump for an air mattress to force short bursts of high pressure air in through the intake pipe while the heater is turned on. That blows the soot out of the combustion chamber and exhaust pipe so the heater can breath again. Tons of white smoke comes out during this process and if that smoke gets on your face and clothes they will instantly be covered with soot. Use the electric air pump to blow the smoke away from you during the repair process, and of course, try to stay upwind. I tried running the heater only on the highest setting but the same problem occurred a month later.
If you purchase a diesel parking heater I highly recommend buying an electric air mattress air pump as well. The soot build up on the glow plug is error code #8.
Chinese Diesel Heater Error Codes
| ERROR CODE | ISSUE | SOLUTION |
| E-01 | Undervoltage of power supply – battery doesn’t have enough power | – Recharge your battery before turning the diesel heater back on |
| E-02 | Overvoltage of power supply – voltage is over the permitted level | – Reduce the voltage to 12 volts |
| E-03 | Glow plug fault – ignition plug failure | – Check glow plug and leads (replace if necessary) – Possibly low voltage |
| E-04 | Fuel pump fault – fuel pump broken/ not working | – Check the fuel pump’s getting power – Check all fuel lines are intact – Check there’s enough fuel in the tank – Possibly low voltage |
| E-05 | Overheating of the machine | – Check air intake isn’t blocked – Check all vents are unblocked – Check fan is working correctly – Check that ducting hasn’t been crushed – Check the temperature sensor on the housing |
| E-06 | Motor fault – fan motor issue | – Check that the fan is turning freely – Possibly low voltage – Check the magnet polarity and Holzer sensor position [see video below] |
| E-07 | Broken circuit fault – communication broken between the heater and controller | – Check all plugs and connections – Possibly low voltage |
| E-08 | Flame out – low fuel or air in fuel lines | – Check fuel levels in fuel tank – Check fuel filter is full – Check for blockages in fuel supply – Check all fuel connections are good – Possibly low voltage – May need to restart multiple times to refill fuel |
| E-09 | Sensor fault | – Check sensor plug isn’t loose/ broken – Check the circuit |
| E-10 | Ignition failure | – Check lines & pump for blockages – Check fuel supply – Indicates multiple restarts without success (due to other errors) |
Radiant Heating Systems
If you can afford the cost and are willing to do the labor, radiant heating is a great way to go. You can now buy 12-volt systems which pump heated liquid through tubes placed under the floor. This provides consistent heating without fan noise and your floor will always be warm on your bare feet.
Cooling
Air Conditioning, Fans and Windows
Air conditioning is expensive up front, with typical prices starting at about $1,200 US and going way up from there. All air conditioners run on electricity and they draw a massive amount of power. They often take up a lot of roof space and protrude downward from the ceiling, reducing headroom. Some units mount under the floor, but they all suck a ton of power. Most camper vans don’t have air conditioners due to the expense of both the unit and the solar equipment required to run them. With the exception of hot days over 85 degrees F (30C), well placed fans and open windows can often provide adequate cooling.
Ceiling fans can be purchased which are able to blow air both in or out. I thought having one fan blowing air in while another blows the air out would work well, but if doesn’t really, at least not on really hot days. I ended up keeping the doors open and blowing air in from both fans, but when it is really hot the only solution is air conditioning.
A single, well placed fan in combination with open windows can provide a comfortable cross-breeze on warm nights. For this reason many people position the fan above the bed and crack open windows on either side. There is a tradeoff to consider if you can only use one ceiling fan, and that is wanting to use the fan to blow out the vapors produced when cooking. If you plan well enough you can position the ceiling fan above the cooking area and still have it pull air in from windows near the bed.
RV ceiling fans seem way overpriced considering that regular fans cost 1/5th as much. I wanted the cheapest fan that would blow both in and out, and I wanted two of them so the expense doubled. I paid about $130 each and the fans seem decent, but if you spend more you can get one with a remote control and even a temperature sensor to turn the fan on and off automatically. You don’t want to have to get out of bed to turn the fan on and off if you can avoid it. There is also the issue of having to manually open and close the vent cover that keeps the rain out and the heat when it is cold outside. Having the fan over the bed makes these adjustments easier, but if you can afford the automatic versions you can put the fan above your cooktop and open windows by the bed.
You will definitely appreciate having a portable fan which can be moved to wherever you will be spending your time. Some run on 12-volts and others are rechargeable.
Windows that open cost a lot more than windows that don’t open, often more than double the price. You need to install the windows early on in the build process and the impact on you budget will be significant. Cost is dependent on size, but average around $350 for solid glass and about $700 for a large window that can be opened somehow. Spend even more and you can buy windows with screens and shades built in, sometimes just at the bottom. Van windows are usually tinted black for privacy and that works great during the day. At night you need blackout curtains because people can see inside when there is more light inside than outside.
Windows turn out to be an important factor in heating and cooling because they can provide ventilation, but they reduce insulation. The more windows you have the more energy you will need to use for heating and cooling. Insulated black-out curtains are essential for both privacy and insulation from the heat and cold.
Next up is Van Build #6 – Beds, Seats and Cabinets
Van Build #1 – Observations and Suggestions