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tnum
12-14-2017, 06:07 AM
Hey everyone!

I'm new to sprinter vans and new to this forum - just picked this one up yesterday. 2006 Passenger.
https://i.imgur.com/8WN4cCJ.jpg

I'm trying to figure out how the aux heat should work and what I should expect it to do. I've used the search features (here and Google) and was able to find this diagram of the coolant system: https://i.imgur.com/ms5oJX6.png

Which looks to me like the first stop after the aux heater should be the heat exchanger in the dashboard. Is this only when the engine is running and if it's just the aux heater then it flows backwards to warm the block first? My issue is that I either don't know how to use the aux heat, I'm expecting it to do something it doesn't do (warm the inside of the van), or it's not working the way it should and is maybe plumbed backwards?

This is what my dashboard looks like and the controls I have available and I'm expecting (hoping) to be able to run the aux heater to warm the inside of the van as well as the engine block.
https://i.imgur.com/yobxI36.jpg
https://i.imgur.com/SpUtX3X.jpg

I can get the aux heat to turn on and I hear the fuel pump clicking as well as the turbine type sound of the furnace and can confirm that exhaust is coming out of the little exhaust pipe in the left front wheel well. Also, I can feel the some of the water hoses are warm after running the aux heat for a bit but the air from the vents still blows cold.

Furthermore, following the warm hose from the aux heater...

It starts here and the warm side is on the right:
https://i.imgur.com/Mxike2F.jpg

Then up the inside of the fender, warm on the top:
https://i.imgur.com/Dg4xZGi.jpg

Then across the firewall and behind the brake booster, warm on top:
https://i.imgur.com/AYdDEbG.jpg

And then into this thing - which looks like it might be number 2 (water pump?) on the diagram I linked to above:
https://i.imgur.com/LqawOaL.jpg

Which ends up leading to the engine:
https://i.imgur.com/OTRDx6B.jpg

The side that was cold leads straight to the heat exchanger in the dashboard... which seems to me, according to that diagram, that it is pumping backwards and will have to heat the entire cooling system up to temperature before it will blow warm air inside the van.

Anyone have any thoughts? Or can confirm how this is supposed to work?

Thanks! :)

P.s. Just got this engine code too... anyone have any common reasons to see this I can check?
https://i.imgur.com/ua9m8EZ.jpg

Patrick of M
12-14-2017, 01:06 PM
Re Espar. Is it running? U can hear it if it's running. The red wavy lines on the controller means it wants to run, not that it's running. That controller can be modified to do diagnostics so if it's not running that is your first step.
The climate controls on a Sprinter are not that intuitive, read the owners manual
When it is cold out the recirculating option must be used (and reset every25? Min) or exterior cold air will come rushing in.

ECU
12-14-2017, 04:17 PM
A couple of ideas...It can not heat your van unless you turn the temperature knob up. I suggest all the way.
One other part that fails and causes no heat is the auxiliary water pump. You probably have a picture of it but your pictures are so big, I can't find it. The pump is inline on the fire wall. If you have everything else running and you can not feel the vibration of the pump running, it is dead. This will cause a lack of heat unless the engine is running.

tnum
12-14-2017, 06:03 PM
Re Espar. Is it running? U can hear it if it's running. The red wavy lines on the controller means it wants to run, not that it's running. That controller can be modified to do diagnostics so if it's not running that is your first step.
The climate controls on a Sprinter are not that intuitive, read the owners manual
When it is cold out the recirculating option must be used (and reset every25? Min) or exterior cold air will come rushing in.

I definitely hear something running that sounds like a turbine/furnace and it's blowing hot air out the little exhaust pipe behind the front left tire. I've gone through the owners manual a couple times and it doesn't help that my vent selector dial seems to be broken/jammed. Does the recirculation need to be activated prior to the van being turned off?

A couple of ideas...It can not heat your van unless you turn the temperature knob up. I suggest all the way.
One other part that fails and causes no heat is the auxiliary water pump. You probably have a picture of it but your pictures are so big, I can't find it. The pump is inline on the fire wall. If you have everything else running and you can not feel the vibration of the pump running, it is dead. This will cause a lack of heat unless the engine is running.

Sorry about the picture size, I don't know why they were so big and when I first posted this they just showed as urls but I have since fixed them.

I definitely had the temperature knob up... the settings in the picture are how I had everything.

Is this the pump you're talking about? If so it's either very smooth and quite or not running.
https://i.imgur.com/532IRRz.jpg?1

Any insight as to where the fuse might be?

tnum
12-14-2017, 06:12 PM
All the fuses in the steering column fuse box are good at least.

autostaretx
12-14-2017, 06:27 PM
Given the 7 day timer, the simplest way to test/run your Aux heater is to simply push the red button (with the wavy lines).
Engine off.

That should start the 2-hour cycle: the display on the timer will wake up, showing 120 minutes and the wavy lines ("operating").
You should hear a click-click-click as the heater's fuel pump gives it fuel (but that requires that your tank be over 1//4 full).

The heater should then spool up and start working... the exhaust is in the left front (US driver's) wheel well.
Expect clouds of white smoke until it warms up a bit.

It will continue to burn at full tilt until the coolant temperature reaches 180F, at which point it will drop to idle.
It will maintain the 180F until the 2 hours are up.

Your cabin fan will also come on at speed 1, unless you've got the speed knob turned up higher.

The operation of the front panel is covered in the Owners Manual (available here: http://diysprinter.co.uk/reference )
There's also an Espar guide there which describes the plumbing and valving. http://www.diysprinter.co.uk/reference/espar_sprinter_manual.pdf

--dick

ECU
12-14-2017, 07:58 PM
Yes, that is the pump and if it isn't running, there is no way for the heat from the espar to get anywhere. It is easy to replace (when things are cool).

Douglas Hicks
12-14-2017, 08:29 PM
You can get a VW auxilliary water pump. The Dodge/FL and VW pump are physically the same, just the wire connection are different. the FL/Dodge pump is more costly than the VW pump. The wiring is not the same, so you will need to cut the wiring off the old pump. Using quick connectors, splice the old wire connector to the new pump.

tnum
12-16-2017, 12:14 AM
Thanks everyone - is there a quick way to test the pump to make sure it's not a fuse/relay?

I'm assuming a 12v +/- on the terminals would do it but I figured it's worth asking incase there some special MBness about this pump.

Also, did anyone have any ideas about the P0088 code about the common rail fuel pressure being too high? Could this somehow be related to using the aux heater?

autostaretx
12-16-2017, 12:21 AM
Thanks everyone - is there a quick way to test the pump to make sure it's not a fuse/relay?

I'm assuming a 12v +/- on the terminals would do it but I figured it's worth asking incase there some special MBness about this pump.
That should be safe, it's just a normal 12v pump.

Also, did anyone have any ideas about the P0088 code about the common rail fuel pressure being too high? Could this somehow be related to using the aux heater?
Unless your heat problem is really due to a damaged wiring harness (shorting across to the pressure sensor's wiring) there is no relationship between the two systems.
The aux heater gets its fuel via a private tap at the tank, has its own fuel pump, and has no effect upon the engine's fuel system. Especially the high-pressure end of it.

--dick