Xantia 2.0l 1994 Heater Trouble

jamescw · Post by **jamescw** » 30 Oct 2005, 10:13

I have a 94 2.0l Xantia, the problem is that the heater does not blow hot air. There is a screeching noise from behind the dash which i suppose is the drive to the control flap within in the box, i have checked the drive motor on the lower flap and all ok. The heater motor works fine high an d low speed as normal. Can someone confirm that there is an electronic control flap at the top of the heater box (central windscreen area) and also whether there is a cut off valve for the water to the matrix so that i will know if hot water is constantly circulating through the matrix. Also the thermastat is working ok as the pipe in to the matrix is hot and the out let is also warm but not sure if that is due to engine temp as it runs along behind the Cyl Head area. Unfortunately i know that i have to take the dash out but would be grateful of some guidence so i know which area to look at.

Appreciate any help on this

Thanks

James

Post by **Peter.N.** » 30 Oct 2005, 10:29

The usual heater arrangement is for the water to flow continually through the matrix, the temperature being controlled by a flap, either manually or electrically, so the water returning from the heater should be as hot as that going in if the heater is not functioning. If it isn't, you could either have a blocked or partially blocked matrix or you could have air in the heater. If you remove the return pipe, and with the engine running pour water into the header tank until you have a stream of water free of bubbles coming from the pipe. The alternative is of course, that the flap is not moving.

jamescw · Post by **jamescw** » 30 Oct 2005, 10:42

Thanks for the reply, will try and flush the matrix and hope for the best... really dont want to have to take the dash out.

Kind regards

James

Clogzz · Post by **Clogzz** » 30 Oct 2005, 11:30

Taking the dash out is only for when the matrix leaks.
The most likely problem is air in the heater.
There is a bleed screw at the top of the heater hose to let the air out.
Open the screw with the engine running, and close when fluid starts to come out.

mezuk04 · Post by **mezuk04** » 30 Oct 2005, 12:28

Glad to see you joined laddy

Peter Mannn · Post by **Peter Mannn** » 01 Nov 2005, 14:12

I have the same model Xantia. From experience, I recommend (once you have the heater sorted) to use a coolant with at least 33% glycol. Keeps the the coolant system at a lower pressure. This reduces risk of the dreaded heater matrix leak.

jamescw · Post by **jamescw** » 01 Nov 2005, 19:56

Thanks for the replies, most helpful. This Saturday is the day when its fix the problem thats been annoying me for months time, so hopefully ill have good news.

Thanks again for the help

James

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