Espar cabin heater not working in cold temps

[jmfife]

sailnimble@yahoo.com How is the new heater working?
We are also having issues with our original D4s not starting reliably. I would love to pull up the diagnostic code related to the heater using the central controller like you did. Can anyone describe how do do that? It sounds like there is some info in a service manual but I am not sure which one or where in the manual you found the info. Can you point us to it?
Thanks!
Mike Fife
Bend, Oregon

 

[Kiltym]

sailnimble@yahoo.com How is the new heater working?
We are also having issues with our original D4s not starting reliably. I would love to pull up the diagnostic code related to the heater using the central controller like you did. Can anyone describe how do do that? It sounds like there is some info in a service manual but I am not sure which one or where in the manual you found the info. Can you point us to it?
Thanks!
Mike Fife
Bend, Oregon

See: https://sprinter-source.com/forums/index.php?threads/90933/

 

[tarpondale]

I would add that while insulating the van wall under awning window behind driver seat which requires removing back seat and wall panel. I unknowingly separated the warm air duct leading to the front vent from the T, the fairly rigid duct is inside a insulating spongy foam so not visible. then after enough uses and time the foam separated and blocked off the return air hole behind wall panel which lead to over heat lockout. this is how we learn, right?

 

[jmfife]

Thanks guys - regarding my heater's failure to start reliably....
I got the Autel. I tested it this morning (~25 degF) and it did the common thing - white smoke, tried twice to start, and failed. Using the Autel, I got code 100 - "Auxiliary heater does not start."
It is interesting I have noticed that the heater starts more reliably when the engine is on. Do you think this could be because of the higher voltage? This morning, the camper battery voltage was 12.8V, and the voltage at the Espar (per the Autel) was 11.0V. Normally when the vehicle is running, the alternator is controlling to 13.5V or so, and connected to the house batteries, so the voltage is higher in that case. Anyone else noticed their Espars starting easier when the engine is running? There was a comment on one of the forums about OneManVan determining that the wire gauge to the heater was too small, and he doubled it. But I can't seem to find that post.
Thanks for any info!
Mike

 

[OrioN]

Thanks guys - regarding my heater's failure to start reliably....
I got the Autel. I tested it this morning (~25 degF) and it did the common thing - white smoke, tried twice to start, and failed. Using the Autel, I got code 100 - "Auxiliary heater does not start."
It is interesting I have noticed that the heater starts more reliably when the engine is on. Do you think this could be because of the higher voltage? This morning, the camper battery voltage was 12.8V, and the voltage at the Espar (per the Autel) was 11.0V. Normally when the vehicle is running, the alternator is controlling to 13.5V or so, and connected to the house batteries, so the voltage is higher in that case. Anyone else noticed their Espars starting easier when the engine is running? There was a comment on one of the forums about OneManVan determining that the wire gauge to the heater was too small, and he doubled it. But I can't seem to find that post.
Thanks for any info!
Mike

Seems either your house battery is no longer holding a charge, is not fully charged, or the wiring to the Espar is weak. The Espar draws ~9A for the first 3 minutes for the glowpin. That is why you are seeing 11.0V, and the heater is negatively responding to this low voltage.

 

[jmfife]

It's warmer today so I diagnosed my intermittent Eberspacher starting issue a little more.

CODES
Attached is the Autel screenshot showing the codes I pulled a week ago for the Airtronic. Note these codes do not seem to correspond to Eberspacher codes from the Airtronic troubleshooting guide. At first I thought the Autel codes were the octal versions of the Eberspacher codes but that doesn't seem to correspond either. It seems instead the codes are being translated - by the Westy windshield computer (Operating and Display Unit)??? Just guessing. I must be totally missing something here. I see in the Westy schematic an ERROR SIGNAL wire blue/white going from the heater to the Operating and Display Unit. That seems to correspond to the diagnostic wire on the Eberspacher per the troubleshooting guide. Does anyone know if there is there a master list of codes that corresponds to what we read from the Autel? I would think it would be in the Westy Electrical and Repair manual but I don't see it. I don't have the CD though - just a PDF with no wiring diagrams.

ATTEMPT TO START
I cleared the codes with the Autel and started the engine and saw the house battery go up to 13.6V or so, and the Autel was reading 13V from the heater. But it whitesmoked badly and didn't start. I checked the error codes and there was only one: 0100 - Auxiliary heater does not start. Any ideas what to check next?

 

[Kiltym]

Remove the unit, service it, and reinstall. There are youtube videos on servicing other Espar models, all similar. Lots of posts here and all over the internet about Espar white smoke.

Check for carbon in the burner tube and replace if unable to remove all of it (which is not easy).

The code text matches the Espar manual pretty clearly. The numbers are not the same as you have noticed.

 

[jmfife]

Well I just found this which purports to show all control module codes for NAFTA Sprinters 2000-2007 by Eric J. Ord. It's out of print, but there is a digital scan of it online here.
The Auxiliary Heater code section is attached.
Looks like 0100 - failure to start can be a lot of things. About half of them are related to fuel supply. I will probably start troubleshooting from this list next time I get a chance.

 

[jmfife]

Thanks for the suggestion - I already took it apart and did the atomizer area service recommended in the youtube video and replaced the glow plug. But I stopped short of opening and cleaning the combustion chamber because there wasn't much carbon in the atomizer area. I don't think this heater has seen much use. But based on your suggestion, I will check the combustor next time I have it out. Thanks!

Remove the unit, service it, and reinstall. There are youtube videos on servicing other Espar models, all similar. Lots of posts here and all over the internet about Espar white smoke.

Check for carbon in the burner tube and replace if unable to remove all of it (which is not easy).

The code text matches the Espar manual pretty clearly. The numbers are not the same as you have noticed.

 

[Kiltym]

We had to replace our burner tube due to white smoke and non start issues. It was very hard to see the buildup at the bottom end of the tube (very small pieces), but some were present. We replaced the burner tube and everything worked like new. We replaced with an Espar tube (~150), but there are chinese knockoffs at a fraction of the price that might be worth a try.

Also to note is Espar changed the design of the burner tube and our units have the older style. The newer style is supposed to reduce the carbon issue as I understand it. Time will tell.

You can also try running kerosene through the heater as there are reports that can clean out the burner tube. We did this also (for about an hour on high), before replacing the tube, with no luck. But it has worked for others though.

 

[onemanvan]

We had to replace our combustion chamber due to white smoke and non start issues. It was very hard to see the buildup at the bottom end of the chamber (very small pieces), but some were present. We replaced the chamber and everything worked like new. We replaced with an Espar chamber (~150), but there are chinese knockoffs at a fraction of the price that might be worth a try.

Also to note is Espar changed the design of the burn chamber and our units have the older style. The newer style is supposed to reduce the carbon issue as I understand it. Time will tell.

You can also try running kerosene through the heater as there are reports that can clean out the chamber. We did this also (for about an hour on high), before replacing the chamber, with no luck. But it has worked for others though.

FWIW: Nomenclature - combustion chamber is the large cast aluminum part with fins whereas the burner tube is the small stainless steel part with the fuel line attached to it. From what I've read running kerosene through the heater for 30~60 minutes on high heat helps remove the fluffy carbon buildup in the combustion chamber but doesn't do much good at removing the hard baked on deposits at the base of the burner tube. Those deposits are hard to see and almost impossible to remove - but they're what often results in 'failure to start' accompanied by white smoke.

 

[Kiltym]

FWIW: Nomenclature - combustion chamber is the large cast aluminum part with fins whereas the burner tube is the small stainless steel part with the fuel line attached to it. From what I've read running kerosene through the heater for 30~60 minutes on high heat helps remove the fluffy carbon buildup in the combustion chamber but doesn't do much good at removing the hard baked on deposits at the base of the burner tube. Those deposits are hard to see and almost impossible to remove - but they're what often results in 'failure to start' accompanied by white smoke.

Thanks. I updated my post to be more accurate to avoid confusion.

 

[jmfife]

OK thanks for the input everyone! I ordered a new burner tube and fuel filter. Looking for the next opportunity to remove and re-service the heater. Will let you know how it goes. Really love winter camping so need to get it figured out. . Our backup propane catalytic heater works but mostly results in warming the upstairs bunk area and not so much the bottom living area. It's hard the beat a working Airtronic in the winter!

 

[jmfife]

Made progress! Disassembled it again and found the little startup air hole in the burner tube was blocked by what appeared to be a mixture of dirt and diesel oil. I should have fully disassembled and cleaned the burner the first time. Then I would have noticed this. It's not possible to see it by just removing the glow plug and cleaning the cavity and replacing the atomizer. I really needed to spend the extra 10 min to fully disassemble the heater and pull out and inspect the burner tube. I replaced the burner tube for good measure.

Tested it this weekend and it started no problem, although it did shut down on over-temp twice when I had it set to 72 degF and the heater was cranking at 100% for a few minutes. Then, when I reset it, it did blow some white smoke on startup. When setting the heater to a reasonably low setting (60 degF overnight), it started and ran like a champ all night. Also it did fine in the morning when I cranked it up to 70 degF.

To address the over-heating issue, I will first look into the inlet and outlet air ducting. Seems a likely culprit given what others (like @tarpondale) found when opening up the side panel in their camper regarding the duct work. The heater can't measure air flow rate to my knowledge, so a house air duct restriction could conceivably cause over-heating. I guess it's also possible the blower is not performing at 100%, but I think there is a sensor on that and would expect for it to throw a code if that were the case, plus I would think that would throw off the fuel-air mixture. Maybe the over-temp sensor needs to be replaced (I guess I should have done that at the same time as the service.). But overall guessing house air duct restriction of some sort is most likely. But that's just an educated guess. Will let you know what I find.

At least it starts and runs now!

Mike

 

[Pnwsquid]

The vast majority of Espar problems are restrictions based on either the cabin air or combustion air side. If you hooked up the heater without any ducting, or without restrictive exhaust/combustion intake it would run without issue for an extremely long time.

With this in mind, the Westy install is not ideal.

The sharp angles of the ducting from the heater to inside of the van, as well as the questionable combustion intake are a problem. The cabin air intake also pulls in a lot of dust/grime and being that it is behind the driver side panel I believe it is a bit choked up from the factory as well.

If anyone is having issues with these heaters staying running (obviously a different issues if it wont start at all) I strongly suggest running the heater with the ducting disconnecting from the outside, including the cheesy intake tube that pulls air from the inside of the mounting box housing.

 

[OldWest]

Mod Idea: Convert Front Air Outlet to Air Inlet

The front air outlet behind driver seat sits right above the air intake floor hole (behind the gray plastic panel.

Intake air flow comes from the body cavity behind the gray plastic panel (including the air vent openings beside bench seat) and down to the floor opening which then has duct to the Espar heater.

The air outlet duct sometimes sags on top of the air intake floor opening, and restricts air intake.

Remove and close off the duct to this front outlet. Then either leave front outlet open for air intake or add duct work (rectangular to circular), and even some HVAC filter material.

Or could just shorten the air outlet duct with a new outlet closer to bench seat (beware too much heat on legs, blocking off, etc.).

The air outlet comes from Espar heater rear, up to beside the bench seat to a T connector, with one branch going forward and one branch going to kitchen and bathroom.

Concerns would include sufficient heated air distribution with only kitchen and bathroom outlets, sufficient air flow in remaining one branch ductwork so Espar heater doesn't shutdown thinking air restriction, other?

 

[Pnwsquid]

Mod Idea: Convert Front Air Outlet to Air Inlet

The front air outlet behind driver seat sits right above the air intake floor hole (behind the gray plastic panel.

Intake air flow comes from the body cavity behind the gray plastic panel (including the air vent openings beside bench seat) and down to the floor opening which then has duct to the Espar heater.

The air outlet duct sometimes sags on top of the air intake floor opening, and restricts air intake.

Remove and close off the duct to this front outlet. Then either leave front outlet open for air intake or add duct work (rectangular to circular), and even some HVAC filter material.

Or could just shorten the air outlet duct with a new outlet closer to bench seat (beware too much heat on legs, blocking off, etc.).

The air outlet comes from Espar heater rear, up to beside the bench seat to a T connector, with one branch going forward and one branch going to kitchen and bathroom.

Concerns would include sufficient heated air distribution with only kitchen and bathroom outlets, sufficient air flow in remaining one branch ductwork so Espar heater doesn't shutdown thinking air restriction, other?

Here is what I did, much more simple than deleting an (important) outlet.

There is a lot of vacuum in the new intake. Sucks a cleanux from several inches away.

 

[jmfife]

Here is what I did, much more simple than deleting an (important) outlet.

There is a lot of vacuum in the new intake. Sucks a cleanux from several inches away.

You guys (@Pnwsquid and @OldWest) are right on! I did a qualitative test with the main interior air inlet connected and disconnected at the Espar. The outlet flow rate increased a bit (just noticable) when I disconnected the corrugated inlet tube at the Espar. So there is definitely some restriction in the intake path design. Also I watched the thermistor resistance decrease (using the Autel live measurements) when I disconnected the inlet so disconnecting definitely resulted in a cooler combustion chamber due to the increased air flow rate. I think the Westy design of the air path puts the Espar right on the edge of over-temp when the heater is cranked at 100% for a significant period, ingesting fairly warm air, and especially when the bathroom outlet is closed.

Mine has not over-temped since my first test after installation. Used it 4-5 times now and it starts reliably and runs great so I think I will just continue with the stock setup. I rarely dial the heater up very high anyway and if I do, will make sure I have the bathroom outlet open.

By the way, the hydronic heater on our rig is working again. Just cleared the codes with the Autel and have been exercising it this winter. It's really nice to have it to pre-warm the Sprinter and as a backup in case the Airtronic flakes again.

By the way the Autel has been AWESOME. It's a little clunky to use but being able to read the codes, clear codes, and see live data is a game changer.

 

[Kiltym]

We use our heater almost every night right now (and have used for many years). Stock setup. Has never overheated (except when running at high altitude with the low altitude pump). I am not sure there is a big benefit to changing the stock setup, but maybe I am missing something. Obviously if the inlet gets blocked somehow it needs to get fixed, but rerouting or adding a piece that would definitely get broken off in our van seems like overkill. We do always keep all outlet vents open and unobstructed.

Personally the design seems to be fine to me.

 

[Pnwsquid]

We use our heater almost every night right now (and have used for many years). Stock setup. Has never overheated (except when running at high altitude with the low altitude pump). I am not sure there is a big benefit to changing the stock setup, but maybe I am missing something. Obviously if the inlet gets blocked somehow it needs to get fixed, but rerouting or adding a piece that would definitely get broken off in our van seems like overkill. We do always keep all outlet vents open and unobstructed.

Personally the design seems to be fine to me.

Of the 5 Westy’s that I am in close contact with in my area, all of them have had issues with the heaters.