Heater booster/aux/espar

[Abcd123]

Hi guys, first time posting.

I’ve recently bought a 2004 208 Sprinter. Had a problem with power and found intercooler was leaking. Replaced this.

yesterday after switching engine off I heard a noise sounding like jet engine. It turned off after around 30 seconds. Did some research on this forum and traced it back to a box beneath the battery behind driver headlight (RHD- UK).

I’ve turned the button off inside so the noise has stopped.

However my heater doesn’t really warm up very much, even with that unit on. I think it may be the coolant circulation pump, but I don’t want to be changing things that are not needed. What could cause my heater to not warm up very much, also I’d like to know bit more how these extra diesel powered heater work and how to test it. Also what is causing my heater to not get warm.

 

[Patrick of M]

So much info on the Espar on this site. You’re doing good though if it sounded like a little jet engine it was running. And if it was running while the engine was off the coolant pump is functional. The controls for the heat jam up and get broken quite a lot it might be that as well . Even with the Espar it takes about 10 minutes to warm up the van without the Espar it takes much longer.

 

[Abcd123]

Thanks, yes the forum is great, glad I found it.

the espar only runs for around 20/30 seconds afte the engine switches off, is this normal or should it run longer?

also is a blocked heater matrix possible (had this of a 1999 ford transit).

 

[Nautamaran]

Yes, this could be clogged core, but more likely a stuck heater valve?
There is a bypass valve on the coolant return flow that directs heat into the cab. Follow the two hard pipes above the battery... they loop down through the Boost Heater: one comes up from the EGR, the other crosses the engine and Tees - one leg continues and feeds the dash heat and the other “bypass” hose drops down into the engine via the bypass valve. (LHD layout is likely somewhat different but the circuit will be the same?)


The valve is normally in the “heat on” position, and moves to the “heat off” position when power is applied (assumes the electronic dash a/c control). Grab the hoses up under the windshield lip and judge where the hot fluid is going (or not going). Note that the “top vents” above the radio do not deliver heat, but do deliver cooled air if the a/c is running (I don’t claim to know why...)

The Espar Boost Heater is controlled by the “bow tie button” between a/c and REST button. The REST system runs the dash fan at low speed with the aux coolant pump running. This warms the cab while parked, using residual engine heat. Pressing the REST button with the engine off is a convenient way to check your aux coolant pump - feel the pump, located downstream of the EGR coolant line, near the battery. The Espar (Eberspacher) furnace cycles with the key and takes about 30 seconds to shut itself down.

Unrelated: you may also notice a high pitched whine from the battery side of the engine, immediately after stopping. This is likely the EGR valve going through its normal cleaning cycle.

-dave

Added: it’s just occurred to me your UK van may lack an EGR valve, but the aux coolant pump will still be down there feeding one of the hard lines that run behind the battery.

 

[Cheyenne]

Hi Abcd and welcome from a fellow Brit!!!

The Eberspacher, or Espar for short, diesel fired heater only runs when the engine is actually running so what you are hearing after turning the engine off is the heater going through its shutdown procedure.

With the engine running and the button pressed, red light on, feel carefully around the small exhaust in the N'/S front wheelarch for evidence of the heater working. If the exhaust is hot then you are already on to a winner! these units often fail through lack of use.

Now feel the two steel pipes running up the inner wing next to the battery, one should be significantly hotter then the other, again a good sign.

Finally feel the pump on the firewall (bulkhead) down behind the battery and you should be able to feel it running.

My 2004 can get warm air from the heater during winter in two to three minutes with the Espar running whereas it takes half an hour without!

Let us know how you get on.
Keith.

PS Where are you in the UK?

 

[Patrick of M]

A correction to what I said above....I thought you meant the Espar continued running after your shut down the engine (some vans can run the Espar with engine off either because they came that way from the factory with a timer, or because they have been modified to do so). What you were hearing was the shut down routine of the Espar.
So: the Espar will run while engine running with a bad aux coolant pump as the main WP circulation is enough to keep it happy, you may need to look into the aux coolant pump.

 

[Abcd123]

Hi guys. Thanks for replies. I can confirm the exhaust was hot and there was gases coming out. Seems as though it’s running well. Bothe pipes near the battery are equally hot (not too hot, can comfortably touch them)
However even leaving it start for 30ish mins still no warm air...confused now. Forgot to check the circulation pump...will get on to that tomorrow.

Cheyenne: I’m based in Bolton (Lancashire/Greater Manchester)..my vans converted into an ice cream van lol.

 

[Abcd123]

On a side note..for those of you in UK...where is the best place for spares?...genuine or copy parts?. Also are there any specialist (for sprinters) around Manchester...(don’t need anyone yet..just good to find these people before I actually need them)

 

[Nautamaran]

A working Boost Heater? Nice!
Your best sleuth work will be while the engine is just warming up and you can trace the coolant flow by warm/cold hoses... Don’t forget to feel for heat in the bypass/heater matrix hoses coming off the Tee joint up under the windshield/wiper deck, behind the a/c plenum:


You want to confirm that the heater bypass valve is operating properly, and not stuck in the “no heat” (energized) position.

-dave

 

[Abcd123]

Hi I’m struggling to get around which hoses to check To see if the heater valve is working. I’ve attached some pictures. Please could circle or point out which pipes I need to check to test if the heater valve is working.

 

[trc.rhubarb]

Mine is mounted right here, but i have a US left hand drive... so maybe it's moved a bit in yours. I dont see the valve anywhere but it should be right where that metal T is at.




Ignore the tubes in my photo

 

[Abcd123]

I’ve just checked there and can’t find it...anyone else keno where it is and which pipes to check. Thanks

 

[Abcd123]

Bump...come on guys...I’d like to have a go at the heater myself before taking to a garage but don’t know which pipes to check. Help...

 

[Patrick of M]

if you could take a shot from further away of the same area you don't have the same configuration of me so it's hard for me to see what's going on. That being said the pump is where item that needs to be replaced every so often. and you could bench test it if you want just isolated and attach some hoses and power to it and see what happens.
the North American configuration of the heater valve is such that if there's no power to it defaults to full-on but I'm not sure about the Euro version

 

[autostaretx]

Normally, if the circulation pump isn't working, the Espar will (over)heat the water that's in its "boiler", which will then trip its over-temperature switch and shut it down. From "cold" that takes about 3 minutes.
So if the espar continues to happily run for many many minutes, i would expect some pump somewhere is working.
(if the engine is running, it's the main coolant pump being run from the belt)

--dick

 

[trc.rhubarb]

Find the hoses that go up into the cowl... follow them down to the aux pump... between the cowl and the pump is the valve, although it is looking like your valve may have been replaced with that metal t fitting if not relocated. Given that the hoses are in the same spot, i'd expect the valve to be as well. it's also possible your pump has been removed, as some people think that's a necessary preventative measure but no idea why.

The valve is pretty easy to disassemble, clean and grease to full working condition again. Just be careful not to break the plastic tabs. a bit of water pressure in it from your faucet once the 4 screws are out and it pops apart. I've found debris (rubber) in the valve and corrosion on the piston in the solenoid. Both easily remedied for free and almost no effort.

 

[Cheyenne]

It looks as though you have an added heater possibly in the rear of your ice cream van conversion. The 'T' shown in your photos with worm drive (Jubilee) clips is not MB fit!

I assume you only have manual heater controls, one dial for heat showing red/blue, another for airflow direction and the third for the eSpar on/off. If so I doubt you will have the control valve being mentioned by all the members in the USA who seem to have automatic temp control (ATC).

Have you checked the electric pump located on the firewall down behind the battery is actually running?

Keith.

 

[Abcd123]

Hi Kieth, your right, I’ve just remembered the engine coolant is used to heat up our water supply for hand washing ect. Grrr...just adds more to the confusion. Im off ton row so will be taking a look at all the pipes.

dick, the problem I’m having at the moment is that there is no heat inside the van,with and without the espar running. The espar does stay on for more than 3 minutes.

 

[Cheyenne]

Hi Kieth, your right, I’ve just remembered the engine coolant is used to heat up our water supply for hand washing ect. Grrr...just adds more to the confusion. Im off ton row so will be taking a look at all the pipes.

Try clamping one of the pipes running to your added heater and see if this improves the performance of the cab heater. You may have 'stolen' too much flow from the original heater. A 'Girling' or similar brake hose clamp is very effective at clamping heater hoses without damaging them.

Keith.

 

[Abcd123]

Hi I’ve clamped the water heater pipe but still no heat. Without the clamp both pipes are warm (not too hot).