One of the biggest challenges for many expediters is how to keep warm in the winter.

It’s a challenge especially for those in Sprinters or cargo vans – how to keep warm during the winter. Some people idle their truck, but that’s not very cost effective. It uses a lot of fuel and puts a lot of unnecessary wear and tear on the engine. Some people just tough it out using zero degree mummy sleeping bags and flight suits and electric blankets. Whatever floats yer boat, I guess. Others just get a motel room, but that can get expensive. Some will run an electric space heater off a generator, but that requires the generator to be on full load most of the time, using a lot of fuel, and requires frequent oil changes in the worst weather. The two most popular methods are the propane heaters like the Mr Buddy Heater or the gas and diesel heaters like the Espar or Webasto heaters.

The advantages of the Mr. Buddy heater are the low up-front costs and the relatively low daily and weekly operating costs. You can get a Mr. Buddy heater, all the necessary hoses, connections and filters, and a couple of 20 pound propane tanks for less than $300. Two 20 pound tanks will last between 50 and 220 hours, and most people will get about 140-150 hours, on the average. So they will keep you warm for relatively little money.

The disadvantages of the propane heater are not to be ignored. One of the biggest is having to carry and store two propane tanks and a propane heater. They take up room and you don’t want them being hit by an overzealous forklift operator, especially if you are foolish enough to not have the lines disconnected from the heater while you’re being loaded or unloaded. You need to disconnect the lines from the heater when the heater is not running. Although most people do, you’re not supposed to sleep while the heater is running, either, which if you follow those guidelines becomes a major drawback of having the heater in the first place. Another big one is that you’re not supposed to store or operate propane tanks inside an enclosed space, like inside a house, garage, basement, shed, cargo van, if the tanks are larger than 1 pound bottles. That’s another disadvantage that most people ignore. There’s also the “mess with it” factor of having to constantly connect and disconnect the lines, having to keep the lines clean and free of oil from the propane, changing the filter periodically, and having to refill the tanks at the most inopportune times, because they never run out when you don’t need heat. They’ll run out in the middle of the night when it’s 3 degrees and snowing and there’s no propane available where you are parked.

The advantages of the Espar Airtronic heater is they are brain-dead easy to mess with, about the same as central heat in a house – you turn it on and set the thermostat and forget about it. It’s about the size of a loaf of bread, so it doesn’t take up much room. It gets its fuel directly from your vehicle fuel tank, and gets its power from your auxiliary battery or battery bank. It has four modes: Boost, High, Medium and Low, and will automatically cycle through whatever mode is required based on the thermostat setting. It will put out a lot of heat very quickly, and unlike the radiant heat of most propane heaters, it is a forced air heater with some serious air flow. There are diesel and gasoline models, the D2 and the D4 being for diesel, and the gas B2 and B4 being the most popular for vans. It uses an average of one amp per hour from the auxiliary battery, and uses about .06 gallons of fuel per hour (gas models use about .10 gallons per hour). Depending on how cold it is and how well insulated your van is, it’ll go through about a gallon of fuel every 12-15 hours when the temperature is below freezing, and obviously less than that when it’s above freezing. It uses round duct hose, much like a clothes dryer exhaust hose, so you can put the heat directly where you need it, including the use of “Y” fittings to split the heat output between the front and rear of the van.

The disadvantages of the Espar are largely cost related. Depending on where you buy it the D2 will cost about $1000 and the D4 about $1500, give or take. If you have someone install it, add $500. You will also need an aux battery, but unless you are running inverter loads of more than a light or two, laptop, and other small loads, a $125 marine deep cycle battery is plenty. If you have heavier amp hour requirements, then a more robust true deep cycle battery, like an AGM battery, which can run $300 to $500 depending on your amp hour requirements. You’ll also need to have a battery isolator or combiner/separator if you want to charge the aux battery from your alternator. But if you already have an aux battery setup, it’ll work with the Espar just added right on to it. The Espar is a direct 12-volt connection, just like a roof vent fan or other 12-volt loads. So the initial costs can be a lot, but when you do a cost analysis you find out that the longer you keep it the cheaper it gets.

Over the course of a five or six year period it becomes as cheap or cheaper than running a propane heater. In my case, including the cost of the D4, installation, all repair costs over the years, plus the cost of fuel using $4.00 a gallon, it has cost me 36 cents an hour to operate, which is cheap for heat that keeps me warm enough to sleep on top of the covers, naked, in zero degree temperatures.

Below is a rundown of my experience with the Espar D4 as of September, 2013 when I had some service done on it. It should give you a good idea of what to expect with one, and a means to compare costs and methods of keeping warm and toasty.

Over the 6 years I’ve had a few repairs here and there, fuel pump, the thermostat (rheostat, actually), I’ve replaced the blower motor twice, the burner tube once, and after 3 or 4 years I preemptively replaced the glow plug (yes, it’s a little diesel engine with its own glow plug and everything). Also replaced the tail pipe a couple of times.

All in all, considering the number of hours this thing has been run, that’s pretty awesome. And the number of hours is significant. They don’t see many Airtronics with this many service hours, mainly due to people replacing older units instead of repairing them, and with people getting new vehicles. It’s certainly not because these units don’t have those hours in them to begin with.

Here’s the rundown:

Times are Hours:Minutes
Start phase – 791:27
High – 1,195:31
Medium – 4,653:55
Low – 9,051:02
Adjustment – 2,536:28
After-run – 546:01
Power ON – 1,023:40
Ventilate – 652:49

Operating hours counter total – 20,450:53

A little explanation of these things. First, that’s just a snotload of hours. 20,450 divided 6 years is 3,408 hours a year, divided by 6 months is 568 hours a month, divided by 30 days is 19 hours a day. So, yeah, I run it a lot, and while driving, a lot.

The Start phase is the Boost period where it’s putting out lots of heat to quickly heat up the truck, then it quickly drops down to the other heat levels.

The Adjustment phase is where it’s not quite at one level or another, and it in between levels working to adjust itself to another level.

When you shut the heater off it goes into the After-run phase where it vents the heater, burns the remaining fuel in the chamber, and cools everything down.

The Power ON phase is where the heater is on, but it’s not actually producing heat. The thermostat controls this. It happens when it gets warm enough for the heater to effectively shut itself off.

The Ventilate phase is where the fan-only is running. I’m apparently one of the very few people who run the fan without the heater being on. They normally see a number that’s a fraction of that, just a few hours.

If you look at the numbers closely you will see that mine spends half of its heated running time at Low. That’s a testament to having the van well insulated. They don’t often see a heater with that high of a percentage on the lowest level. It’s also a factor if the increased airflow of the D4 as opposed to the D2. In identical situations, and in most installations, the D2 will spend the bulk of its operating hours one level above that of the D4. If the D2 is on Medium, the D4 will be on Low, for example. This is due to both the increased BTU output and the increased airflow of the D4.

Some people like the inside of the vehicle warm when they sleep (me) and some like it cooler. Those who like it warm and aren’t very well insulated will see theirs running on High or Medium most of the time. I tell people all the time, “Insulate your van like you’re going to live in it, because you are.”

If your van (especially) or truck is well insulated, the 24 hour amp draw of the Espar D4 heater is only about 24 amps, as it’ll average about an amp per hour. The D2 will be just about the same, maybe slightly higher, but not enough to worry about. You don’t necessarily need a high end, high capacity AGM battery for that, but you absolutely, positively do need an aux battery for that, not a cranking battery, not hooked to your starting battery or batteries. Just a simple Group 31 truck or “marine” battery (they’re the same thing, just different terminals) will suffice. Two or more if you are running small (a.k.a. not a fridge) inverter loads off the house battery. Starting batteries are for starting, house batteries are for everything else – don’t confuse the two by thinking you can do both with one type of battery, even if your truck has 3 or 5 truck batteries. Use the truck batteries for the truck, use the aux battery for everything else.

Espar Specifications

AMP Draw
D2 – 8.3 amps
D4 – 8.3 amps

D2 – 2.8 amps
D4 – 3.3 amps

D2 – 1.9 amps
D4 – 2.0 amps

D2 – 1.0 amps
D4 – 1.1 amps

D2 – 0.7 amps
D4 – 0.6 amps

FUEL CONSUMPTION, Gallons per hour
D2 – .07
D4 – .13

D2 – .06
D4 – .10

D2 – .04
D4 – .07

D2 – .03
D4 – .03

D2 – 7,500 BTU (2.2 kW)
D4 – 13,650 (4.0 kW)

D2 – 6,150 (1.8 kW)
D4 – 10,200 (3.0 kW)

D2 – 4,100 (1.2 kw)
D4 – 6,800 (2.0 kw)

D2 – 2,900 (0.85 kW)
D4 – 3,400 (1.0 kW)

AIR FLOW, Cubic Feet per Minute
D2 – 48
D4 – 85

D2 – 40
D4 – 69

D2 – 27
D4 – 50

D2 – 19
D4 – 30

Looking at the total Costs Per Hour, it continues to go down with every hour. But taking current total costs and total hours, it comes out as follows:

Figures include parts, labor and taxes.
11/7/2006 – Espar Heater including installation – $1,989.82
4/27/2007 – Extra Duct Work and Fittings – $124.39
10/15/2009 – Fuel Pump/Filter, Glow Plug, Extra Duct Grille – $459.44
1/26/2010 – Thermostat Mini Controller – $211.65
12/17/2010 – Blower Motor, Tail Pipe, Gaskets, Glow Pin Screen – $528.83

That totals $3314.13

Divided by 20,450.88 is 16.2 cents an hour.

The most recent repair was:
9/27/2013 – Blower Motor, Burner, Tail Pipe, Fuel Filter – $784.07

Expecting no more repairs over the next two winters, using the average hours it’s been run thus far, assuming a total of 27,268 hours in after those 2 years, the Cost Per Hour at that time will be 15.029 cents per hour.

So, in my case, running it for 12 hours x 16 cents costs about $1.92, plus .05 gallons fuel per hour (.6) times $4.00 per gallon($2.40) in fuel is $4.32. Or, $0.36 an hour all in.

If you want to stay warm and comfortable all winter long, particularly if you are in a van, there isn’t a better or more cost effective solution than that of an Espar heater in my opinion. I’ve never met anyone who has had one and then went back to not having one. There are certainly other options, but none of them are as good, or as cost effective as the Espar. They work, and they work extremely well. And, as it turns out, for a whole lotta hours. 20,000 and counting.

Stay warm out there!