Auxillary Heater

[tamrsoft]

If it looks like yours then it must be the same type of unit. I will check the fuse box tonight, puzzled why your fuse 17 should have been taken out, maybe previous owner wanted it permanently disabled.

 

[fuzzer]

its a great wee gadget , my engine is over 40 degrees in 4 min on -2 and -3 mornings.

 

[Dunhamkid]

its a great wee gadget , my engine is over 40 degrees in 4 min on -2 and -3 mornings.

Do you notice any difference in fuel consumption using the heater?

 

[fuzzer]

Do you notice any difference in fuel consumption using the heater?

ehh , not really , difficult to tell cause my car is always in traffic when cold. Maybe 1-2mpg off the top of my head.

 

[Wezzel]

Mine is definately a diesel heater. Perhaps it is faulty because it stinks when it is running and kicks evil smelling diesel fumes out from under the front offside corner of the car. I also seem to get 2 or 3 mpg less than normal. I turned it off last winter, soon after I bought the car, and haven't put it back on since.

 

[Rory]

Do they all work like this? I've got a 54 reg C270CDi, and I'm sure I've read that if aux heating is selected on the cars convenience menu then it uses the a/c compressor in reverse. I do have it enabled, and it does get warm pretty quickly.

 

[tamrsoft]

Puzzled as to how it can run the A/C compressor in reverse without the engine running backwards.
I have checked out the piccies on the MB WIS CD Manual for 'Auxiliary Heater ' and the unit shown is definitely diesel driven and very different to the pictures shown of my unit so as Dunhamkid states, mine must be electric.
Comment for Dunhamkid - my fuse 17 (indicated for Auxiliary Heater) was also removed but I did notice that the fuse position did not have any contacts in it so it would serve no purpose putting a fuse in that position anyway. I have a feeling that the device that we have is not called an Auxiliary Heater but something else, but what ? What amazes me most is that the last people to know or understand are the MB Service Dept.

 

[Dunhamkid]

Puzzled as to how it can run the A/C compressor in reverse without the engine running backwards.
I have checked out the piccies on the MB WIS CD Manual for 'Auxiliary Heater ' and the unit shown is definitely diesel driven and very different to the pictures shown of my unit so as Dunhamkid states, mine must be electric.
Comment for Dunhamkid - my fuse 17 (indicated for Auxiliary Heater) was also removed but I did notice that the fuse position did not have any contacts in it so it would serve no purpose putting a fuse in that position anyway. I have a feeling that the device that we have is not called an Auxiliary Heater but something else, but what ? What amazes me most is that the last people to know or understand are the MB Service Dept.

Tamrsoft

Very observant!! My fuse 17 contacts are also missing but only one of them. I suppose I will have to get my meter out when it gets cold and check the power supply to the heater. It may "sing" like a kettle when it starts to heat (?)

What have I started?

 

[fuzzer]

I can hear a difference in the engine tone when its cold with the heater on

 

[Dunhamkid]

I can hear a difference in the engine tone when its cold with the heater on

That will be due to the extra load on the engine from the alternator

 

[Dunhamkid]

Puzzled as to how it can run the A/C compressor in reverse without the engine running backwards.
I have checked out the piccies on the MB WIS CD Manual for 'Auxiliary Heater ' and the unit shown is definitely diesel driven and very different to the pictures shown of my unit so as Dunhamkid states, mine must be electric.
Comment for Dunhamkid - my fuse 17 (indicated for Auxiliary Heater) was also removed but I did notice that the fuse position did not have any contacts in it so it would serve no purpose putting a fuse in that position anyway. I have a feeling that the device that we have is not called an Auxiliary Heater but something else, but what ? What amazes me most is that the last people to know or understand are the MB Service Dept.

Tamrsoft

Although in my original post I called it an "auxillary heater" , the hand book describes it as a "booster heater". Check out your MB WIS for a "booster heater" and see what it comes up with

 

[Midland45]

I think the booster heater system fitted to diesels, is simply an electric heater unit in the coolant system. It can be set in one of the menus to operate if the temp is below 6 deg C. This will allow the engine to reach normal operating temperature more quickly, however the trade off is more drag via the alternator and thus slight drop in mpg. But of course the mpg increases as car reaches normal operating temperature, so its difficult to ascertain the total effect on mpg. It does of course lead to usable warmth in the interior faster though.

 

[Dunhamkid]

I think the booster heater system fitted to diesels, is simply an electric heater unit in the coolant system. It can be set in one of the menus to operate if the temp is below 6 deg C. This will allow the engine to reach normal operating temperature more quickly, however the trade off is more drag via the alternator and thus slight drop in mpg. But of course the mpg increases as car reaches normal operating temperature, so its difficult to ascertain the total effect on mpg. It does of course lead to usable warmth in the interior faster though.

Can you elaborate on how you set this unit to operate in one of the menus? I can't find that info in my car manual. The only control appears to be with the switch situated next to the cigarette lighter

 

[DieselE]

Can you elaborate on how you set this unit to operate in one of the menus? I can't find that info in my car manual. The only control appears to be with the switch situated next to the cigarette lighter

In the W211 it does not appear in a menu. The only way to stop it operating is put the climate control into economy (no compressor). It might be the same or similar in yours. Mind you there's no switch on the W211.

 

[Rory]

Puzzled as to how it can run the A/C compressor in reverse without the engine running backwards.

I meant reverse function (ie heating rather than cooling) rather than literally running in reverse!
However I may have dreamed up this whole thing - possibly misled by the fact that the booster heater can be turned off by pressing the A/C off button. (I am *sure* I read that it does use the a/c compressor to add heat, though)!

 

[Midland45]

On my W209 Diesel, if my memory serves me correctly there is a heater menu with 3 settings. Automatic, off and A/C off. I think the A/C off position allows you to switch the booster heater on or off from the A/C off button, perhaps this is where the confusion lies.

 

[Paul64]

I must admit, my 1992 W124 500E is a little behind on the newer technology however, the reverse operation of the A/C compressor would be an excellent way of producing heat quickly.
Many of the A/C units for shops and houses work on the same principle where the compressor runs normally but valving in the gas lines change the direction of the gas so it runs to the evap first rather than the condenser which, being in the air ducting, heats up as soon as the compressor turns.

Maybe it's not like this at all however, it's a great idea anyway!

 

[Dieselman]

Many of the A/C units for shops and houses work on the same principle where the compressor runs normally but valving in the gas lines change the direction of the gas so it runs to the evap first rather than the condenser which, being in the air ducting, heats up as soon as the compressor turns.

Maybe it's not like this at all however, it's a great idea anyway!

These are called heat pumps and are very efficient due to the heat actually coming out of the air (or ground depending on type). They use approximately 25% of the energy of a traditional heating system.

I think Glojo has one for his pool.
http://www.calorex.com/company/pool01.htm

Even very large buildings can easily be heated by a heat pump.

 

[starfinder]

This is a photo of the unit in my car, can anyone confirm whether this is an electric or diesel powered unit.

This unit is a 1.5KW electric heater. It is turned on when the cooling water is below +70C and outdoor temperature is below +7C. :bannana:
BR Starfinder

 

[Dunhamkid]

Starfinder
Can you elaborate as to what controls turns the heater on, ie relay etc