A load of hot air

[hemi01]

I've followed with interest the recent thread on VN V6 heater taps.

I've checked mine and it appears to work OK. The solenoid operates with the heater temperature dial and the arm pushes out when the temp dial is moved off full cold towards warm. I'm thinking that this opens the heater pipes to hot water.

The problem I have is that even with the temp dial in the full cold position I get warm air (much warmer than outside) through the vents when the position dial is in the fresh air position (12 o'clock).

This is most noticable with the air cond off but I suspect that it also comes through with the air cond on and causes the cool air to not be as cool as it should be.

Does this fresh air pass through underbonnet and heat as a result or could the heater tap have an internal leak, passing hot water through the heater plumbing even with the tap off?

Is anyone right across how the heater works in a VN?

[immortality]

you need to get your head under the steering wheel and take a look behind the heater controls. when you turn the heater control you will see a steel shaft turning a small white plastic arm. when turning the heater control to full cold it should push that little arm against a valve (black). that valve controls the vacuum to the heater tap and stops hot coolant entering into the heater box inside the car.

http://forums.justcommodores.com.au/...ntrols-001.jpg

it's a bad pic but you can see the white plastic arm and to the left is the valve

[commsirac]

Ive looked at the photo supplied by immortality and not really sure what Im looking at.

Is the heater tap immediately before the heater with no heater hose between them?
It certainly sounds like you have hot water leaking through the tap.
Id suggest doing some feeling around under the bonnet with the heater hoses, the one that goes in and the one that goes out. The one that goes out should be noticeably colder(even stone cold after ten minutes of driving) if you have the tap closed. If its getting warm coolant is flowing. Even the top hose(heater hose from the top of the motor) shouldnt be getting very hot near the tap, but after along drive, just conduction from the water in the hose will make it so.

One thing you can do is actually block off the top hose, if its not part of a feedback loop and see if it stops the hot air flow. There are hose clamps(look like tin snips) that can be used for this purpose, reputable aircon places would have them on hand.

the only other slim shot, is that you have air leaking out of the rear seal of the bonnet and getting dumped straight into your fresh air supply. If this was the case, putting the airon recirc would see that prob disappear.

[hemi01]

Thanks for the help fellas.

I will check the cool side of the tap tomorrow after driving. The prob does go away in recirc position. I will also check the bonnet seal but I think that's OK because in fresh position cool air comes out the facelevel vents and hot air through the foot vents. If the seal was faulty I'd expect hot air through both levels.

Cheers, Mick