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Hello... Not a good couple of weeks for me! Last week an expensive service, and now my heating packs-up!

The fan is still spewing out lots of lovely cold air, but nothing hot will come out at all (nothing even remorely warm!)..... Does anybody have any idea what could be wrong?

Thanks

Does the fan work on all speeds?
If the fan only works on one or two of the settings the motor may be faulty and require replacing.

Have you tried bleeding the air from the system?
The Mk2 & 3 heaters have a bleed valve near the heater matrix, find the valve and open it slightly (enough for air to escape) and leave it open until fluid comes from the hose.

Are the hoses connected to the heater?
Obvious I know, but you'd be surprised what some mechanics do on a service.

These are the only things I can think of from past experience with VW heaters.

Hope this helps.

Thanks Bluebaron... that is certainly of help!

My only problem now....where can I find the heater matrix? I've also managed to lose my Haynes manual!!

Thanks again.

Loosing your heating is not good. There is air in the system, the heater matrix is among the higest part of the system, so you lose heater first. Either that, or the cable for the mixer is just not moving it from cold.

Exactly why you have air in the system is a big worry. Check that your coolant is at least up to the min and take the cap off (when cool) to see if there is any vacuum or pressure in it.

I say worried about it because head gasket failure is about the only cause for spontaneous air lockage. Failing that, take it back and insist that they bleed the coolant system properly. No sense in doing it yourself if they have been fiddling with it.

Well done JWC!!! The problem is now solved!!

Reading your post it occurred to me that it is going in tomorrow to have the water-pump replaced as it was leaking.... but I had no idea that it was losing water as badly as it was!! It was completely void of coolant! 2 litres of water later the wonderful feeling of heat is back in the cock-pit!

Thanks again, very much appreciated.

James

You need to make sure that you have the correct amount of coolant additive too. The G12 stuff from VW is great because it never needs changing, but make sure its the 40% concentration that it needs to be, otherwise it will corrode inside your engine, never use only water.