Heating System and Mechanisms

[griff430]

I was poking around in the passenger footwell yesterday to try and fix the faulty heating/cooling selector valve (the mechanism is sufficiently bust, which means that if I select cooling, the only way to get heat back in the cabin, is to give the valve a helpful 'nudge'). Whilst trying to fix this, I noticed a couple of drips of anti-freeze around the heater pipework joints. I think it's only a matter of time before I end up with a flooded footwell, so I figure that I should address the leak, and while I'm at it, I may as well swap the valve too, because the system will have to be drained.

Has anyone got any tips for draining the Griff cooling system (apart from the usual - keep the heater fully open etc.) How much should a new valve cost, and where's the best place to get one? I'm also going to change the rubber piping around the heater valves, while I have the system drained. Is this standard piping, or do I need TVR specific stuff?

Thanks,

Dan.

[IPAddis]

I was poking around in the passenger footwell yesterday to try and fix the faulty heating/cooling selector valve (the mechanism is sufficiently bust, which means that if I select cooling, the only way to get heat back in the cabin, is to give the valve a helpful 'nudge').

Could be the valve, could just be the variable resistor attached to the valve. Try taking the motor part off the valve (after marking the position) and see if it still sticks when not connected.

Whilst trying to fix this, I noticed a couple of drips of anti-freeze around the heater pipework joints. I think it's only a matter of time before I end up with a flooded footwell, so I figure that I should address the leak, and while I'm at it, I may as well swap the valve too, because the system will have to be drained.

I had a few drips of coolant in the footwell but a quick tighten of the jubilee clips has sorted it for over 2 and a half years.

How much should a new valve cost, and where's the best place to get one?

Between 30 and 50 quid each if I remember correctly.

Ian A.

[rolfe]

Hi Dan,

When you have got the valve off could you let me know were the microswitches mount. One of mine is dangling down and I know now that this controls the switch but for the life of me I cannot work out how it fits to the valve.
Thanks
Dave

[davidn]

Rolfe,
I was having a root round in the passenger footwell and found a microswitch located on the side of the heater box. It is position just underneath the motor operating the air direction from screen to feet. It seems to be there to stop the motor continually rotating. Check and see of you have one, if not this could be your dangler.
David

[rolfe]

Cheers David,
Problem is it definatly controls the heater valve but the valve just hangs from the heater hoses so I cannnot seehow it to mount it on the heater box. The valve has one movement controlled by a micro switch on the back of the valve but I cannot see behind it and do not want to have to drain the system to find out!
Dave

[griff430]

Rolfe, I think my heater valve is suffering from the same problem as yours (maybe that's why the valve seems to have a mind of it's own?). The valve just seems to hang in mid air, supported only by the hoses.

IPAddis, is it easy to remove the motor from the valve?

Dan.

[IPAddis]

griff430 said: Rolfe, I think my heater valve is suffering from the same problem as yours (maybe that's why the valve seems to have a mind of it's own?). The valve just seems to hang in mid air, supported only by the hoses.

IPAddis, is it easy to remove the motor from the valve?

Dan.

The valve does hang in mid air supported only by the hoses. That's why it's ability to act as a curry hook is sadly limited.

The motor assembly including the variable resistor and microswitches attaches to the valve by a combination of Mechano pieces and a bolt in the centre which mounts onto the valve spindle. Never taken it off completely but it doesn't look that hard.

The first think I did was to remove the variable resistor from the air recirculation valve (which was working properly) and swap it for the one on the heater valve. That was you isolate either the variable resistor or the heater ECU.

In my case changing the resistor made no difference and I'm hoping it was a loose connector at the ECU (which I've since dismantled and reassembled).

Ian A.

[griff430]

OK, thanks. I'll have another root around in the footwell.

Dan.

[Rolfe]

Just had a look at my valve and it looks like Mr Bodger has been there before me. I have mounted the switch in the correct position but although the mechanism hits the top microswitch it cetainly goes no where near the bottom micro. To make lifre worse there is a resistor in the wire between the two cables which I have managed to snap. Anyone know how to change these and were you get them from?

[Rolfe]

Hi Dan,
I have located the motors/gearboxes from RS components the big electronic outlet. £ 32.00. Let me know if you want the details.
Dave

[griff430]

Rolfe,

Yes, I'd be interested in the details please. I haven't had time to stick my head in the footwell since I made this post, but if it turns out that the mechanism is knackered, I'll be on the phone to RS.

Thanks,

Dan.

[rolfe]

Hi Dan

RS components parts number is 1 178 4800 at www.rswww.com 01536 201201. I have also got the diodes if you need any as I had to buy a pack of ten. E mail me you adress from my profile if you want a couple.
To get it off I simply removed the bottom hose to drain the system. Put an old towel over the electrics before removing the unit as residual water does spill out. Feel free to contact me if your stuck as I am a bit of an expert with these now!!!!??????
Dave