Heater blowing hot & cold together?
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Heater blowing hot & cold together?
A friend of my Daughter has just got her first car, a 306 Diesel.
The only fault with it seems to be the heater which blows cold air on the screen, footwell & face vent on one side while the other three face vents blow hot. Everything else is normal,the air direction & hot/cold controls work ( when its in cold they're all cold) I've ruled out a matrix or airlock fault as the three face vents get quite hot, wierd or what?
The only fault with it seems to be the heater which blows cold air on the screen, footwell & face vent on one side while the other three face vents blow hot. Everything else is normal,the air direction & hot/cold controls work ( when its in cold they're all cold) I've ruled out a matrix or airlock fault as the three face vents get quite hot, wierd or what?
406 HDI Exec Estate (2 off) & 307CC HDI Cabriolet
Re: Heater blowing hot & cold together?
If the matrix has inlet and outlet pipes on the same side, it could be an internal blockage or something stopping hot water getting to the other side. The vent piping could also be dislodged on one side. Unfortunately I suspect it could well be a dash-out job
<steve_earwig> I think this forum is more about keeping our cars going with minimal outlay than giving our cars more reason to go bang
- neildavies
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Re: Heater blowing hot & cold together?
We had these same symptoms when we had our 306, it was a leaking heater matrix. Unfortunately, the dashboard has to come out to fit it.
Probably not the answer you wanted to see, sorry. With us 5 years ago, the part cost about £40 and Peugeot charged about £250 to fit it.
Probably not the answer you wanted to see, sorry. With us 5 years ago, the part cost about £40 and Peugeot charged about £250 to fit it.
2007 Mondeo Titanium X 2.0 TDCi
2007 307cc Sport 2.0 HDi 136
Gone but never forgotten: 2002 406 Coupe SE 2.2 HDi

2007 307cc Sport 2.0 HDi 136
Gone but never forgotten: 2002 406 Coupe SE 2.2 HDi

Re: Heater blowing hot & cold together?
Strange though, no loss of water - no wet carpet - no misted windows & no smell of anti freeze, & it still doesn't explain why she gets hot air from 3 face vents & cold from the other?
406 HDI Exec Estate (2 off) & 307CC HDI Cabriolet
- jameslxdt
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Re: Heater blowing hot & cold together?
sounds like a dodgy matrix, does it have a/c?
FAQ - 406 D8 petrol (excl. V6) running and starting problemsPeugeot wrote:what are you worried about? we made car that lasted 10 years"..."Zat is very goode non?
- neildavies
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Re: Heater blowing hot & cold together?
I remember we'd still have some heat only on some vents. Also, I don't think we had a lot of water loss.
2007 Mondeo Titanium X 2.0 TDCi
2007 307cc Sport 2.0 HDi 136
Gone but never forgotten: 2002 406 Coupe SE 2.2 HDi

2007 307cc Sport 2.0 HDi 136
Gone but never forgotten: 2002 406 Coupe SE 2.2 HDi

Re: Heater blowing hot & cold together?
No, no air con, it's just a "style". I've not seen a 306 heater unit but with most others all the air is at the same temp, either hot or cold. I can't see how it can have hot from 1 vent & cold from the other?jameslxdt wrote:sounds like a dodgy matrix, does it have a/c?
406 HDI Exec Estate (2 off) & 307CC HDI Cabriolet
- neildavies
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Re: Heater blowing hot & cold together?
Sorry, I can't say how it happens, just that it did the same with ours. My only thought at the time was that maybe the matrix wasn't completely flooded and there was some hot air in it at the top, which was where the "warm" vents were passing through.
You could see if it gets worse, but ours was like it for months. Another symptom I remember was often having condensation on the windows of the car in the morning.
You could see if it gets worse, but ours was like it for months. Another symptom I remember was often having condensation on the windows of the car in the morning.
2007 Mondeo Titanium X 2.0 TDCi
2007 307cc Sport 2.0 HDi 136
Gone but never forgotten: 2002 406 Coupe SE 2.2 HDi

2007 307cc Sport 2.0 HDi 136
Gone but never forgotten: 2002 406 Coupe SE 2.2 HDi

- jameslxdt
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Re: Heater blowing hot & cold together?
not just condesation, but this nasty greasy film on the windows when you get condesation, when cold
FAQ - 406 D8 petrol (excl. V6) running and starting problemsPeugeot wrote:what are you worried about? we made car that lasted 10 years"..."Zat is very goode non?
Re: Heater blowing hot & cold together?
No, no other symptoms at all, wierd !
406 HDI Exec Estate (2 off) & 307CC HDI Cabriolet
- steve_earwig
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Re: Heater blowing hot & cold together?
Maybe there's more than one flap and the cable/actuator's busteddjp30djp wrote:No, no air con, it's just a "style". I've not seen a 306 heater unit but with most others all the air is at the same temp, either hot or cold. I can't see how it can have hot from 1 vent & cold from the other?jameslxdt wrote:sounds like a dodgy matrix, does it have a/c?

Unskilled meddling sin©e 2007
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