Table of Contents
- Espar Airtronic D2 Diesel Heater
- Espar D2 Technical Specifications
- Thermo King - Espar installation
- Troubleshooting and Maintenance
- Clouds of White Smoke when starting the Espar D2
- Connecting a Kerosene bottle to the fuel pump
- Thick clouds of white smoke still appear - partially plugged fuel filter
- Maintenance Time - 938 hours - January 4, 2018 - 10 months after installation
- Maintenance Part costs
- Success - Maintenance Time Reset to Zero - January 5, 2018
- Preventative Maintenance - 607 hours - October 10, 2018. Reset to 0 hours after service.
- Fuel Filter Replacement - 1027 hours - April 19. 2019 - Maintenance hours not reset.
- Atomizer Screen Replacement - 1099 hours - June 22, 2019 - Maintenance hours not reset
Espar Airtronic D2 Diesel Heater
The Eberspacher Espar Airtronic D2 is a safe and economical heater that utilizes diesel from the main Sprinter tank. This unit has unsurpassed safety standards, so there is no concern about carbon-monoxide poisoning, fumes or fuel vapors inside the living area in the van. The unit was professionally installed by Thermo King of British Columbia. It is appropriately sized for this model of Mercedes-Benz Sprinter, which is the high-roof long wheelbase version.
Without any insulation in the van, the heater on high speed struggles to keep the temperature warm inside when the outside temperature is below zero. On the first camping adventure deep in the Mountain Loop highway in April 2017, the temperature outside was -10c and inside the van the maximum temerature was only +5c.
Good Sprinter insulation is important.
Espar D2 Technical Specifications
The Espar D2 technical specifications are found in the table below. The unit is powered by the on-board 12v battery found in the driver side floor. On low power, the number of litres consumed in an hour is 0.1 litres, or just 2.4 litres in a 24 hour period. In that same timeframe of 24 hours, it only uses 8 watts per hour or 192 watts or just 16 amps (192 watts / 12 volts). The 12v Sprinter battery has a capacity of 82 amps, more than enough for the Espar D2 to operate on low temperature for 24 hours straight without depleting the battery.
Thermo King - Espar installation
Thermo King is a global company offering a wide variety of services, including installation of diesel heaters into pretty much any vehicle including Mercedes-Benz Sprinters. If you’re looking for somebody to install a heater, try your local Thermo King.
Troubleshooting and Maintenance
Notes and photos taken the week of January 1, 2018.
Clouds of White Smoke when starting the Espar D2
After about 850 hours of usage, the Espar D2 showed signs of thick white smoke coming out the exhaust pipe upon startup. Once the fuel ignited, and the heater began to work, the white smoke would disappear. Several hours more of usage, even thicker white smoke came out very slowly, and the heater would retry by itself twice before starting again.
Connecting a Kerosene bottle to the fuel pump
Kerosene burns much hotter than diesel, and will normally clear out carbon from the Espar D2.
The fuel pump is at a 15-30 degree angle, and the lower portion of the pump has the input fuel line leading to the diesel tank. There are two circular hose clamps on a thicker piece of rubber tubing. The circular hose clamp closest to the fuel filter can be loosened, and then pulled away from the fuel pump by twisting the rubber tubing back and forth while at the same time pulling away from the fuel filter.
Another piece of rubber tubing goes over a short piece of the clear tubing, place two circular hose clamps over the tubing, then slide the combination over the metal fuel pump inlet. Tighten the hose clamps. Secure the other end of the clear tubing into a bottle of kerosene using duct tape or similar product. You can use a small 1 quart or 1 gallon container.
Ensure that the clear hose is as short as possible, so that the pump doesn’t have to prime the heater as much. Run the heater for about an hour. Then disconnect the temporary hose, and re-connect the main fuel tank hose that you removed earlier.
If thick white smoke still appears upon startup in cold or very cold weather, see the next section.
Thick clouds of white smoke still appear - partially plugged fuel filter
If thick white clouds of smoke appear on startup, don’t despair.
There is a very informative video on a Espar D2 furnace repair guide on YouTube. At the 2 minute mark in the video, he explains that if the fuel filter is partially plugged, it will give you temperature dependant no-starts (like in sub-zero weather) the colder it is the less it runs, and will make the heater bellow with white smoke. Remove the tiny fuel filter, and replace with a new one. Or, if a replacement is not available at the time or repair, remove the filter and clean out very carefully, then reinstall after ensuring the screen and plastic housing are not damaged.
To remove the tiny filter, two different sized wrenches are required, a 12mm and a 17mm. First you need to remove the circle clamp on the black rubber hose that is closest to the pump. Then twist back and forth and pull away the black hose from the pump inlet with one hand, while the other hand holds onto the pump.
One the hose is removed, you will see a shiny metal tube with a 17mm nut, and a 12mm nut to the left.
Use the 12mm wrench on the smaller nut, while turning the 17mm to the left slightly until loose. Remove both wrenches and unscrew by hand. Inside there is the fuel filter.
You can use a pick or any right-angled piece of metal like a right-angled 2mm allen key to dislodge the fuel filter from the pump. Be gentle as to not damage the screen or the plastic housing.
If the filter is still in good condition but clogged partially clogged with diesel varnish or other contaminants, run it carefully over hot water with soap, take some paper towel and gently scrub the outer and inner portions of the metal screen and white plastic. Rinse again with plain hot water to remove all soap and other guck. The clean filter is shown in the next image.
Ensure it is completely dry. Carefully using a compressed air gun to remove the moisture works as well.
Re-insert the undamaged fuel filter, hand screw on the metal tube, then snug the two nuts together with the wrenches.
Connect the hose for your Kerosene tank to the fuel pump, and tighten the circle clamp.
After performing this procedure, run Kerosene through Espar D2 instead of diesel, for about an hour to hopefully burn off any excess carbon deposits in the heater. Then turn off the heater, ensuring the fan is no longer running. Then disconnect the hose for the Kerosene and then reconnect the hose for the diesel. The heater may try to start a couple times, or provide an Error 52 “No Flame Detected” and a red light on the DigiMax D1000 controller. Simply turn off the heater as normal, then restart again. The fuel lines need to be primed and may take 3 or 5 tries. Once the igniter turns on and creates the flame, you should not see any white smoke at all.
Test it once again by turning off the heater, waiting overnight on a sub-zero day, then restart again the next morning. No smoke should appear.
Other procedures should be performed as per the aforementioned video to perform preventative maintenance and keep the heater in excellent functioning condition.
Maintenance Time - 938 hours - January 4, 2018 - 10 months after installation
A couple of days after running Kerosene through the heater, an exhaust smell was apparent inside Discovery. Turned off the heater, then went to a local Espar dealer Cool-It to purchase some basic maintenance parts for the first time. Decided to attempt a complete disassembly of the Espar, saving several hundred doallars in service costs.
Maintenance Part costs
Purchased the following items from the local Espar dealer.
- CAD$6.00 Espar Airtronic D2 Blower gasket
- CAD$11.0 Gasket for Burner, Eberspacher, 2kW, Air
- CAD$15.00 Glow pin screen and insert, Eberspacher All Wattages, Air
- CAD$10.00 Socket for Glow Pin
- CAD$0.00 Metal fuel filter (free)
Intimidated at first, never having performed a complete removal and disassembly before. In the end it was actually quite easy, except for removing the atomizer screen. To remove the screen, a really thin pair of needle nose pliers is required to grab the old screen. Or use a very think pick or flathead screwdriver to pull the screen away from the sides and then pull out the screen. If it’s really carboned up, it will be hard but not impossible to remove.
Once you get the heater out, disassembly is as easy as using a screwdriver.
Won’t go into many details, but the photos shown below display the various stages of disassembly, the old cracked combustion chamber gasket, the very dirty atomizer screen, the carbon dust from the glow pin. Cleaning was performed with a toohbrush dipped in Kerosene, lots of paper towels, a kitchen scrub pad to scrub the outside of the glow pin, and pipe cleaners (from the craft section of the Dollar Store) to clean the burner. An air compressor used to clean out all residual dust from the intake pipe, housing, combustion chamber and burner.
A total of 78 photos follow:
Success - Maintenance Time Reset to Zero - January 5, 2018
Heater started up immediately after re-installing the heater. A slight rubbery burning smell from the exhaust lasted about half an hour. Most likely from the new gaskets and/or the Kerosene used to clean out the old carbon.
Set the heater on high for an hour at 34c maximum temperature. Outside temperature was +5c,
Modified: Sun, 11 Aug 2019 11:56:36 -0700
Preventative Maintenance - 607 hours - October 10, 2018. Reset to 0 hours after service.
See some photos below this post for the second time maintenance has been performed.
Today (October 10, 2018), after 607 hours of service I took my D2 apart once again as a preventative measure. With winter coming soon to the Pacific Northwest I wanted to make sure the D2 was clean and operating correctly.
Bought new gaskets for the blower and burner, and the ignition screen. Took me exactly 1 hour to take the entire unit apart and clean it. I used white pipe cleaners to clean the tiny holes in the burner chamber. A toothbrush to clean the interior fins, along with a bit of kerosene. I used my air compressor to blow out the burner chamber, and a very fine mist of carbon came out.
The interesting part was that the D2 had very little carbon build up overall - almost like it was hardly used. But we do use it a lot (607 hours since January), and many times on low during the night.
I have run Kerosene through the heater several times this year since the last re-build. Also, using the regular diesel, I run it on high at least once a month on the driveway with the doors wide open. I do not use any diesel additives whatsoever. So, running Kerosene once in a while on high heat seems to have kept the unit quite clean overall. We live just above sea level but travel into many mountains on a regular basis with the highest being in Colorado and between Banff/Jasper - about 3,000-4,000 metres.
I have to purchase the 7mm tap tomorrow to remove the screen, and also clean out the existing fuel filter with some warm water and soap, and re-install. Maybe another hour of work to put everything back together again and test it. So, from start to finish it will only be 2 hours worth of work.
Now that I know how clean the unit is after 607 hours, I’ll maybe perform preventative maintenance again after 2,000 hours.
UPDATE: October 11, 2018 - noon
Expecting a struggle with the atomizer screen, I tried to find the 7mm tap at the local Home Depot. Nothing of the sort, and the imperial taps by Ryobi only come in sets and don’t include the 7mm tap required.
Was ready for the hour long struggle with the screen (like I had earlier in Jan 2018), I took a cuticle scraper and purposely bent the top of the atomizer screen a bit so that my small pliers can take hold of something. Used the pliers, pulled up once, and the atomizer screen came out very easily. Wow! Used dollar store pipe cleaners, and tiny bits of carbon came out. I cleaned as much as possible, used compressed air to ensure all loose carbon was removed, and re-installed a brand new screen. Reinstalled all the gaskets and other components, and all was quickly completed.
My guess is that since the unit was relatively little carbon build-up, the screen was not “welded” to the orifice. The screen was dirty, but not clogged like my previous one. I suppose one of the reasons why Espar recommends removing the screen on an annual basis is to help with the removal of the screen.
Still need to install the heater into the van, and clean out the existing fuel filter, connect and test everything later this afternoon or tomorrow.
UPDATE: October 11, 2018 - 5pm
Installed the heater in the van, connecting the fresh air hose to the intake port, and the exhaust pipe to the exhaust port, connected the fuel pipe, tighted everything up, and lowered the heater into place. It’s located just in front of the driver side rear wheel well. Access is easy, its mid-ship so it heats the van as evenly as possible. Using 13mm and 17mm wrenches, I undid the connection at the fuel pump - I needed to loosen the black rubber hose connected to the 17mm nut size. Disconnected the fuel line, grabbed the smallest right-angled allen key and used that to pull out the original fuel filter. Very tiny - took that to the kitchen sink, poured Dawn dish detergent and hot water over it and rubbed it gently in my fingers to clean the very fine screen. Dried it with paper towel and carefully blew it with the air compressor to eliminate all water. Reconnected everything after reinstalling the fuel filter.
Then, I checked the number of hours on the Espar DigiMax-1000 panel, and it showed 607 hours. Again, the reason I performed this service is before winter hits - I didn’t want to be stuck in freezing temperatures without a heater. I started the heater, at max temp of 34c, and let it run for about half an hour. It started up right away, slowed down a bit, the pump stopped ticking, then after a couple minutes started again by itself and ran full speed. The smell of burning rubber was in the air - same as early January due to the new gaskets (most likely). I ensured it wasn’t actually something burning!
After a few hours of heater runtime, there is no more smell, and the heater works like new again.
Fuel Filter Replacement - 1027 hours - April 19. 2019 - Maintenance hours not reset.
The past couple weeks, the heater would only start on the 3rd attempt. Very thick white smoke would come out of the exhaust pipe. This is a common symptom of a dirty fuel filter. See the details earlier in this post of how to remove the fuel filter from the pump.
A metal fuel filter, obtained from Cool-it and meant for a Webasto heater pump fits perfectly in the Espar pump. That was installed, the fuel pipes re-tightened, and the heater tested. No white smoke, and after the heater was primed with fuel (it took two attemps to prime), the heater worked flawlessly.
It has been 1027 hours since the last service was not reset, this way we know how long the heater itself can operate between actual maintenance service. The maintenance interval was changed from 1000 hours to 2000 hours today.
Last week Kerosene was used for about 45 minutes to help burn off any extra carbon within the heater.
Atomizer Screen Replacement - 1099 hours - June 22, 2019 - Maintenance hours not reset
Thick clouds of white smoke still continued well after the fuel filter replacement, and was also harder to start. At the 1099 hour mark, I replaced the atomizer screen. The one inside the heater was full of carbon. This time the heater was not removed from the van, but instead the top portion opened and the screen was removed. The orifices were all cleaned with a pick, and then blown out with a compressor.
Make sure the screen is inserted with the welds OPPOSITE of the fuel intake port.
Once this procedure was complete and everything put together again, the heater works as expected. The maintenance hours were not reset.
Each screen costs about $15 to replace. This gets very expensive over time, so a pack of 10 were purchased on eBay from China for under $10 total. We’ll update our experience. The link to the eBay purchase is here: 10pc Glow Plug Burner Strainer Screen For Eberspacher Airtronic D2 D4 Car Heater
The heater is also run at its highest temperature every month for about 30 minutes to keep it in good service.