No hot air from blowers?

[votivequagmire]

Hi all
My new 320i is turning out to be quite a mozaic of parts.
But I digress for now...

I can't seem to get any hot air coming through the blowers.
Both the pipes feeding the heater matrix are warm but even with the temperature dial to it's maximum it is nowhere near warm.
If I turn the dial fully to the cold position it 'clunks' as if it has reached it's extremity. But nothing happens to the other.
I pulled the cover away and saw the valve that I've heard about lately...
Is there a short and ugly version of this and it's purpose?
How does the dial increase the temperature of the air? Is it a mechanical or electric?

I'm starting to realise why this guy wanted to sell this 320.
I think it used to have a CAT but they've somehow slotted a CAT preparation exhaust on.
If I find the correct exhaust manifold, can I buy the bmw cat preparation front box and replace what they've put on?

Sorry for double problem. The power steering rack had a leak which they failed to mention also. I got a replacement for it for £40 so not too bad.

This exhaust system is gonna cost a little over £200 when it's finished.

[Brianmoooore]

The heater valve only ensures that no heat comes from the heater when the dial is turned to full cold. When the dial is turned to the extreme left, 12 volts is applied to the valve and it shuts off the water flow.
At all other settings of the temp dial, temperature control is mechanical by blending hot and cold air.
Check that the heater pipes are on the correct way around where they connect onto the bulkhead stub pipes under the bonnet. The pipe that comes from the rear of the cylinder head goes to the bottom stub pipe, which is the opposite of what looks right.

[votivequagmire]

Cheers Brian.
Will check it out in the morning.
P**sing down all of today.

[votivequagmire]

Well the pipes look as described above.
Which way does the mechanical control work?
Is there a cable that runs a particular direction from the dial?
If there was a diagram somewhere I could follow it would be helpful.
I wonder if the online epc would show it......

[votivequagmire]

No, nothing to help me there.

[Brianmoooore]

There are four cables that go from the heater controls to the heater box, but their layout isn't the kind of thing you can describe.
If you remove the centre consoles and the side panel from the glove box you should be able to work out what does what by watching as the controls are moved, and see if any of the clips that secure the cable ends have come adrift.

[munky30]

The heater valve only ensures that no heat comes from the heater when the dial is turned to full cold. When the dial is turned to the extreme left, 12 volts is applied to the valve and it shuts off the water flow.
At all other settings of the temp dial, temperature control is mechanical by blending hot and cold air.
Check that the heater pipes are on the correct way around where they connect onto the bulkhead stub pipes under the bonnet. The pipe that comes from the rear of the cylinder head goes to the bottom stub pipe, which is the opposite of what looks right.

You learn (or rather brian teaches) a new thing every day. Never realised it only shut off when the dial was to cold. So the sliders and 1/2/3/4 dial only control the fans?

That would explain why my cabin gets so hot even with the heaters 'off'.

[Brianmoooore]

If your heater produces any heat when the temp dial is to full cold, the electric heater valve is duff or not getting power. It needs 12 volts applied to it to turn it off.

[votivequagmire]

There are four cables that go from the heater controls to the heater box, but their layout isn't the kind of thing you can describe.
If you remove the centre consoles and the side panel from the glove box you should be able to work out what does what by watching as the controls are moved, and see if any of the clips that secure the cable ends have come adrift.

Will have to remove the above then and have a look.
Tried to see by removing black plastic cover on side of glovebox.
Couldn't quite see any movement from temp dial.

[Brianmoooore]

Temperarure blending flap lever is on the right hand side of the heater box.

[votivequagmire]

Well I took out centre console and under dash cover.
All levers and cables seem to be working fine and reaching their respective extremities.
Is it possible that the matrix is blocked?
Or maybe the valve itself?

[mrLEE30]

is the cooling system bled of air? could have same effect and will also eventually knacker your head when it overheats

[Brianmoooore]

Are the pipes to and from the heater getting really hot?

[tommype30cab]

i had this problem, get a jack handle and a hammer, lower the glovebox right down and put the end of the jackhandle against the metal valve, turn heaters to hot and full and, starting gently hit the other end of the handle with a hammer, hit a bit harder but dont risk breaking it!!

if the valve is blocked with rust/limescale this should clear it and unsieze the valve, when i did it i could feel the heaters getting slightly hotter

good luck

[votivequagmire]

The pipes are not really hot.
The car doesn't overheat.

Will try the old 'hit it' technique also.

[votivequagmire]

Still nothing. And the valve seesm to be working perfectly.
Any other suggestions are greatly appreciated??