Heater only blows cold air.

[Rpmayne 0]

Another problem, hopefully with a simple cure if any of you have had the same problem:

 

Heater fan works, coolant pipes to and from the heater matrix are hot, coolant level is good, no hot air regardless of position of the temperature dial.

 

Any ideas.. Thinking it might be the temperature selection mechanism, whats the easiest way to get to it, and hows it supposed to work. Think I remember reading somewhere its cable operated.

 

With the weather recently its been bad not being able to clear the condensation.

[Scott 0]

Do the heater systems in VR's have the one way valve in the heater matrix line like the 16V's - in front of bulkhead?

 

My 16V did exactly the same as you mentioned and it was this valve ..

 

Scott

[Rpmayne 0]

Not sure, just been reading about these valves though a search of the site. Were both coolant pipes to and from the matrix hot when yours was mucking around aswell?

[Scott 0]

Yup they were....

[Rpmayne 0]

Thanks, will get onto VW and see what extortionate price they've made up for them.

[dr_mat 0]

The later cars have the bypass valve in the matrix itself, IIRC.

So if the matrix blows, it bypasses it and allows the coolant to flow back to the engine, but the heater doesn't deposit clouds of steam into your car..

[Kevin Bacon 5]

I think it's your cold/hot air flap.

 

Pull out the passenger side shelf and inspect the bowden cable and flap to see if they're working properly.

[Rpmayne 0]

Ta, will have a look this afternoon. These cars never give you any rest eh? If its not one thing its another.

[PhatVR6 0]

there's a small gear wheel under the airbox in the car. it's designed to break a few teeth off if anyhting gets stuck in the air box.

 

take off the passenger side under tray and see if you can see it, and see if the cbale still operates the flap too.

 

if you can manually move the arm and flap and get heat then it'll be the cable, more likely the heater controls themselves, as they are notorious for breaking.

 

as a side note, never change the direction or heat controls with the fan on anything other than speed one. try it at speed 4, you break things.....

[Kevin Bacon 5]

as a side note, never change the direction or heat controls with the fan on anything other than speed one. try it at speed 4, you break things.....

 

Tell me about it :x

 

This is the 4th time I've repaired mine and it took a new screen vent cable, new panel from a passat and a lot of 'modification' of a few bits. It's held together for 6 months now.....

[Rpmayne 0]

Was as you said kevhaywire, took the heater controls out and a little metal clip fell out. Thats the one which is supposed to keep the outside of the cable fixed which runs to the hot/cold air flap. Think that must have happened when the wiring has been moved around recently.

[Kevin Bacon 5]

Cool. thought as much. Gotta be so careful behind the dash as that is why the heater system keeps breaking. People blame it on cr@p design, but it isn't, it's because alarm fitters fuck around too much behind there and mine even had a huge alarm loom tie-wrapped to the screen flap cable FFS! That is the most tempermental cable of the lot. If that one gets stiff, then the face/feet vent breaks aswell.

 

Bloody alarm fitters. It's about time someone just invented a black box that sits in the boot and all the sensors etc work over wireless. Anything to keep muppets out of the dash area.

[Roger Blassberg 0]

I've just had the dash removed and re-fitted for a heater matrix replacement job, and ever since the twist control for air direction has become very stiff when turning to the screen position. From Kev's message it sounds as though there's a potential failure of the controls.

 

What needs to be done to rectify this? Has the dash got to come out again? If it has, I'll throw it back to the people who did the job, but if it's something I can do releatively easily I will do it myself - I'm fed up with taking it in with one problem and coming home with 2 new ones.

 

Best wishes

 

RB

[Robbo149 0]

I'm fed up with taking it in with one problem and coming home with 2 new ones.

 

RB

 

Story of my life at the mo'! :roll: I keep telling myself everything will work properly one day.

 

Cheers,

Robbo

[Kevin Bacon 5]

and ever since the twist control for air direction has become very stiff when turning to the screen position.

 

What needs to be done to rectify this? Has the dash got to come out again?

 

No the dash doesn't need to come out. Unfortunately, the plastics used to make the main heater box (where the matrix lives) and the controls are a bit on the fragile side. The plastic does not handle heavy handedness at all. If the part is stiff and needs forcing it's not right and stop immediately.

 

What you need to do is make sure all 3 bowden cables are securely clipped to both the heater box and the control panel. The screen cable's clip on the heater box is an arse to get to. I would recommend you buy a new screen cable, it's only a fiver or so.

 

VW realised the factory fit screen cable was too short, so the new one is plenty longer, allowing for a more routed fit. You'll see what I mean when you take the old one off.

 

It's hard to explain this way I'm afraid. The best way is to get behind the dash, remove the control panel and ask any questions from there.

 

So long as you take your time with the heater system and don't force anything, you'll be fine.

 

The blokes that did the matrix probably just ripped everything out half-heartedly and that really Facks me off. I only let mechanics do simple stuff to my car, if at all.

 

K

[Roger Blassberg 0]

Thanks Kev. I assume that it's accessed initially by pulling off the 3 rotary heater controls, followed by the panel behind them, all with great care, and then using common sense. This sounds like it might be a job for a gynaecologist!!

 

I've just got my Bentley manual which may also help me.

 

To be fair, my usual specialist does take care with my cars and will immediately sort it out if there's a minor niggle, but ultimately if you want something done properly............

 

Incidentally, your headlight circuit relay fix went in without a hitch, and together with uprated (standard power) bulbs, the night now holds no fears for me.

 

Best wishes

 

RB

[Roger Blassberg 0]

Further to this, I have noticed that the rate of air flow to the screen is not very high, even on full blast, and is particularly poor to the passenger side. This was true even before the dash was removed for the heater matrix replacement, so it's not as a result of that. I had naively expected that it might have improved as a result of the reinstallation - will I ever shake off this foolish optimism ??

 

Are there some seals on flap valves which deteriorate over time, or is it perhaps that the control cables need adjusting? Maybe the ducting is not properly assembled, or it might just be an inherent design weakness which other people suffer and tolerate.

 

As already detailed above, the screen control cable does need replacing with the new improved version and I'l do that soon, but I would like to improve the demisting flow rate at the same time. Compared to the blower in my similar-vintage Passat, which practically blows the screen out on full chat, it is dreadful.

 

The blower is apparently in good fettle, operating at all speeds and without the moans and groans of past Golfs.The only saviour is that I have air conditioning which significantly improves the demisting performance even at low flow rates.

 

Best wishes

 

RB