Auxiliary Heating (Not!)

nujon · Post by **nujon** » Sat Jan 29, 2011 7:09 pm

Found out today that my new motor has got one of these things although its not enabled on the OBC

The unit, valves and exhaust look "brand new and unused" - not even any sooting on the inside of the exhaust outlet - in short, the unit appears never to have operated. I thought such units operated automatically to boost heating of the engine cooling jacket on cold/freezing days - or are they perhaps totally (software) disabled for the UK market?

X5Sport · Post by **X5Sport** » Sat Jan 29, 2011 7:18 pm

Just replied on your other scanner thread - it should work in the UK.

nujon · Post by **nujon** » Sat Jan 29, 2011 7:58 pm

[quote=""X5Sport""]Just replied on your other scanner thread - it should work in the UK.[/quote]

Thanks - noted

Sanj · Post by **Sanj** » Sat Jan 29, 2011 8:53 pm

Also check the fuse in the glove box... Sorry can't remember which it is, but clearly labelled.

nujon · Post by **nujon** » Sun Jan 30, 2011 10:27 am

Thanks for the replies - I wonder if the engine pre-heat function was only 'plumbed-up' for certain cars - my manual refers only to the cabin heat & windscreen demist attributes - and the plumbing of the unit seems consistent with that ie. to/from the heater matrix

I also drive a C class - on this vehicle the aux heat on/off and timer options are visible on the OBC but no heater is physically fitted - there are some Merc forum grapevines that suggest the heaters were fitted at manufacture in SA but then removed on import by MB UK - the supposed reason being that the units had been implicated in a very significant number of total-loss fires (all makes/models with pre-heaters) and that their removal was an expedient to appease the UK insurance industry against an otherwise big insurance hike which would have affected sales. If true, BMW UK may have gone for the option of disabling the unit rather than removing it. ?

P.S. found the following on the Web - OK it refers to buses but interesting nevertheless:-

Bus manufacturers agree on fire detection systems--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
by Per-Martin Johansson

Volvo Buses and six other European bus and coach manufacturers have agreed to fit all buses and coaches as a standard with fire detection systems in the engine compartment around the auxiliary heater.

According to the public statistics, buses and coaches are the safest mode of passenger transport. The major European bus and coach manufacturers have now joined forces to improve safety even further and adopt suitable measures that take into account the passengers' increasing awareness with regard to the issue of fire safety.

As part of these deliberations, an initiative sponsored by European bus and coach manufacturers has agreed to fit all buses and coaches as a standard with fire detection systems in the engine compartment around the auxiliary heater. Volvo Buses has had this as standard in the engine compartments for several years globaly, but will now also fit it as standard around the auxiliary heater.

These systems have been available for some years on a voluntary basis. The manufacturers EvoBus (Mercedes-Benz/Setra), Irisbus/Iveco, MAN Nutzfahrzeuge AG (MAN/NEOPLAN), Scania, Solaris Bus, VDL Bus & Coach and Volvo, that collectively account for about 85% of the European market, have signed up to a voluntary agreement.

Under the agreement, all touring coaches and scheduled-service buses that are delivered to EU Member States will be fitted, by January 2011 the latest, with equipment that notifies the driver directly and immediately if there is a risk of an expanding fire.

As the vast majority of fires on buses and coaches originate in the engine compartment, the fitting of these early warning systems will avoid passengersâ€™ concerns as well as reduce vehicle damages by enabling a rapid evacuation or even extinction of the fire.

The voluntary agreement covering fire detection systems is open to all bus and coach manufacturers in Europe that have not yet signed up to the initiative â€“ other manufacturers are more than welcome to join us.

Per-Martin Johansson
External Communications Manager
+46 31 3225200
e-mail: [email protected]

ChewingBacca · Post by **ChewingBacca** » Sun Jan 30, 2011 11:20 am

Start your quest by applying 12v to pin 1 to see if the thing actually fires up.

All this is covered in the other thread.

motormender · Post by **motormender** » Sun Jan 30, 2011 12:20 pm

i also went through the nightmare of no aux heater. i could get mine to fire up but not keep going. i would suggest either buying or finding somebody local with a inpa cable to do a diag on the aux heater. this will tell you where the problem lies. i ended up with new battery, new burner and glow assembly, new circlulating pump and the remote relay to get mine working. plus the inpa cable. about Â£400 i think from memory. and hours of messing. Managed to fix the circ pump though if anybody needs one as i have a spare now. try unpluging the power and earth cable first as this resets the heater before you do the power to pin 1 test as if its overheated it wont start with faults stored.
Dave

nujon · Post by **nujon** » Sun Jan 30, 2011 8:20 pm

Further investigation reveals the following:-

Upon unlocking the drivers door or opening or closing either of the front doors - the aux heater makes noises ! :-

1. a steady fan sound (suspect it may draw or expel air via the rubber pipe which runs from the unit and through the inner wing)

2. some secondary irregular intermittant noise - hard to describe

- both noises stop together after ~ 1 minute

The aux heater fuse (No 59 - 20A) - is present and good

Does the above mean anything to members familiar with the heater ?

ITBarbie · Post by **ITBarbie** » Sun Jan 30, 2011 10:23 pm

Hi

I'm probably no help on the second query but I have got the AUC heating on mine with the remote control and at first I just could not get it to work. I tried changing battery in remote and repairing, fuel levels and talking to a webasto dealer locally all with no joy. I had AUC with BMW and took it in. They had to replace the whole unit under warranty in the end all for a pretty penny paid by BMW of course!

As for the fan/whir noise I always get this when I unlock the car for a minute or so.

Penny

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nujon · Post by **nujon** » Sun Jan 30, 2011 11:21 pm

[quote=""ITBarbie""]Hi

I'm probably no help on the second query but I have got the AUC heating on mine with the remote control and at first I just could not get it to work. I tried changing battery in remote and repairing, fuel levels and talking to a webasto dealer locally all with no joy. I had AUC with BMW and took it in. They had to replace the whole unit under warranty in the end all for a pretty penny paid by BMW of course!

As for the fan/whir noise I always get this when I unlock the car for a minute or so.

Penny

Sent from my iPhone using Tapatalk[/quote]

Thanks Penny - I'll have another ratch tomorrow in the daylight - I've read the other thread (very useful indeed) and my current rationale (right or wrong) is as follows:-

1. the heater is a comfort device only (demist, de-ice windscreen & heat cabin)
2. the BMW manual describes only the comfort function - if the device was beneficial to reduce engine wear / improved economy etc. surely it would say so and tell you in normal circumstances not to turn it off (i.e. via the OBC option)
3. the ignition circuit of the device is (sometimes/often) disabled in the UK, via the OBC, for whatever reason (e.g my speculation above)
4. disabling via the OBC was the easiest option - the purge function remains energised however - that's the fan sound on unlocking/opening the doors (thinks you are going to start the car and want the comfort function)
5. MB for eg don't fit these units anymore, if comfort heating is ordered as an option, its an electronic air heating unit (clearly such units won't heat the block!)
6. Block heaters on commercial vehicles / other SUV's (eg Izuzu) are multiple electric elements installed in the block and powered via an independant ~100Ahr 12V battery (also charged by the vehicle alternator)
7. whilst the aux heater on my X5 does not fire-up, the engine reaches normal operating temp within 5 miles of steady 40 - 60 mph driving from a sub freezing start (proved it tonight @ -2C) - who needs a block heater then?

Turks · Post by **Turks** » Mon Jan 31, 2011 2:55 am

[quote=""nujon""]
2. the BMW manual describes only the comfort function - if the device was beneficial to reduce engine wear / improved economy etc. surely it would say so and tell you in normal circumstances not to turn it off (i.e. via the OBC option)
[/quote]

The device will reduce engine wear and improve economy.

Your engine is at its most delicate when cold. The Webasto heats the water and circulates it around the block without any of the engine parts moving. This means that when you come to start your car, it is practically at operating temperature and therefore will be more efficient.

The problem with this is that you have to know when you are going to use your car for the Webasto to do its work and probably need 15 minutes to get the water properly warm. I suppose that is where the remote is handy.

Turks.

nujon · Post by **nujon** » Mon Jan 31, 2011 11:18 am

Least engine wear occurs when the crank pins/journals + big and small-ends + cam-shells and followers etc. etc. (and by association the oil) reach normal operating temperature (bores less significant as spray-lubed and all the rings are expanders)

Heating the relatively small-volume engine water jacket - (bulk of cooling system water is in rad + header + hoses which of course are isolated via the stat when the engine is cold) - will have negligable impact in this respect - you have to run the engine to warm it up. To minimise cold start engine wear, generic advice is to drive away immediately on starting and avoid pushing the unit until it has warmed up.

nujon · Post by **nujon** » Mon Jan 31, 2011 2:04 pm

Just spoken to the Head of Servicing at a large BMW dealership re. the Webasto - very interesting - he commented as follows:-

1. The timed start and manual on/off control for the heater via the OBC is indeed (soft) disabled for the UK market - reasons include that:- (i) it is illegal to run the unit in an unoccupied vehicle on a public road (i.e. as per main engine - UK law apparently does not discriminate) (ii) in recent years, the UK insurance industry has indeed become prejudiced against them re. alleged fire risk

2. BMW will enable the timed start and manual on/off function at the request of a customer - but will stress that such activation is not endorsed by BMW UK and advise the customer to declare the position to their insurance company - who may regard it as a 'modication'

3. Some X5's have the unit programmed to start with the engine if the temp is low enough (the trigger temp can be varied also) - but in others, the firing sequece is totally (soft disabled) - he's seen both - does not seem to be MY related

4. BMW are firmly against the DIY 'hot-wiring' of the unit via T1 and a relay ("by-passes the safety circuits") - dealers see it on occasions when vehicles are brought in for service - in that case they will disconnect the circuit and advise the customer accordingly.

ITBarbie · Post by **ITBarbie** » Mon Jan 31, 2011 3:11 pm

Well I never! Interesting reading especially the legality and insurance. Ive never heard that before. So am k right in thinking that you and I may have the fan whir on unlock but others won't?

Suppose it makes sense re warming important components of car thus increasing initial fuel economy. You've gotta love it though

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nujon · Post by **nujon** » Mon Jan 31, 2011 4:25 pm

Thanks Penny

Digging around indicates that the whirring sound is the Webasto blower - it electrically connects to the heater unit via a flying lead and on the X5, lives inside the inner wing area. Its purpose is to supply air for combustion and also to ~ 60sec purge the unit prior to start up and on shut down. The blower gets a 'get ready' signal from the car on unlocking the driver door / opening either front door - but the unit won't fire until the engine is started, is cold enough - and is otherwise enabled via the OBC (and fuel above reserve and battery volts OK)

IMHO, the unit has no bearing on engine wear or fuel economy (unit of course consumes both fuel directly and high electrical power - which the main engine then has to make up againt the consequently higher e/m resistance of the alternator by using more fuel)

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