Heater problems or should that be no heat!

[rossfergie]

Hello all,

Could somebody help, I have owned my 06 facelift Vectra 1.8 VVT with standard heating and air-con since it was just two years old. The car has been well looked after and regularly serviced I have recently been having issues with the internal temperature in my Vectra no longer being HOT, however, this is an 'intermittent' fault as it sometimes works as normal e.g. I can drive to the shops and its working fine and gets hot, stop the car go to the shop, start the car and it just blows cold!! and may be cold for the rest of the day, get in the car the next morning and it works fine again until I stop the car running. There just doesn’t seem to be any pattern to this other than its cold more times than its hot. The car gets up to temperature about 90 OK and stays pretty constant around this. I am confident its not the Engine Thermostat as I had it changed earlier this year.

Having a read through several threads on the site and seeing references to the air temperature mixer servo perhaps being an issue which could cause this.
I am however struggling to find details of this on the search section which will help me confirm this is the problem. I really am fed up having steamed up windows and being cold!




Thanks all

[tony-1977]

Listen for the mixer servo motor when you turn the temp from hot to cold and back again. Do this with fan on speed 1 and the engine stopped.

Also, what temp does your temp gauge show when running?

[rossfergie]

Thanks Tony, it shows a constant 90 when up to temp ond running and the Rad fan cuts in when it sould I checked that today. I will try listening for the mixer servo motor tomorrow, should I try that when the engine is cold or hot? Thanks Mate'

[tony-1977]

should I try that when the engine is cold or hot? Thanks Mate'

No worries mate. Doesn't matter about the engine temp. The mixer will move with the air temp control on the heater panel

[rossfergie]

Thanks Tony, I will let you know how I get on with it.

[SlowCoach]

He and i are having same issue by sound of it. The mixer valve moves as it should on mine. Cannot access the inside flap. Any ideas on how to access the area? The flaps are next to heater matrix and not sure if i wanna undo the pipes to take matrix out and see if flaps move as should. Once removed, i'll have a hell of a puddle in footwell and be able to see all flaps situ there! But advice is welcomed.

[rossfergie]

It’s taken a few days to get back to you, work getting in the way!!! I listened for the mixer servo motor as you suggested turning the temp from hot to cold and back again. I have done this several times over the past few days but not a sound from the servo motor! and of course still no heat. The engine temp is fine, the gauge is working as normal at a steady 90 and the Rad fan cuts in and out as it should, I can change the direction of the air flow adjustment e.g. from demist to feet only or cabin, feeling and hearing the change in flow so no problems with that. Both hoses going from the engine compartment through the bulkhead wall to the Matrix are equally hot, I have run the system from cold with the header tank cap off to try and see if any air-lock was present, squeezed every hose I could but nothing. Any ideas how much Vx are likely to charge to fix this as I cant go on, not just the cold but the lack of de-misting is very dangerous in this weather. Are there any independent companies who specialise in this sort of heating problems with cars? Thanks in anticipation.Ross

[rossfergie]

Hi All
Just another quick thought, is it possible to bleed any possible air-lock out of the heating system and of so is there as specific bleed screw/valve or area that I need to look for and what is the process?


Thanks

[Ian-Highlander]

I listened for the mixer servo motor as you suggested turning the temp from hot to cold and back again. I have done this several times over the past few days but not a sound from the servo motor!

You've answered your own question, the mixer servo isn't working. You need to replace that, it's a small motor on the side of the air box behind the glovebox, there are a couple of different ones so make sure you get the right one.

[SlowCoach]

Mixer servo is actually driver side, and passager side, but mine works fine passager side. What about driver side?? What should it be doing?? And what is it's job??