heater control dial difficulty

johnbird · Post by **johnbird** » Thu Jan 13, 2011 5:35 pm

took the citroen to work this morning,all went well-so well in fact i have reinterred the roadster in my mothers garage tonight,surely the kiss of death- except for one new problem. whilst it was cold as much heat as possible was the order of the day.today was 11 degrees so i went to turn the temperature dial back a little and it appears the dial is reluctant to stay in any position but wide open.the dial will turn but flicks back to hot when you let go. had a quick look through the faqs and cannot see the answer.is this a regular problem please? any suggestions? im hoping a can of wd40 will cure it but suspect it will involve removing some broken part,thanks,john.

Dollywobbler · Post by **Dollywobbler** » Thu Jan 13, 2011 5:37 pm

A very regular problem. Don't force it with the control or you'll simply snap the cable. There is a thread in the technical about Heater Taps. That's your issue.

johnbird · Post by **johnbird** » Thu Jan 13, 2011 5:55 pm

thankyou,i wil try and find it and read up,john.

kiwi · Post by **kiwi** » Thu Jan 13, 2011 6:15 pm

As has been mentioned plenty of referances to this problem in the forum.

Another thing to mention is it is not so much snapping the cable but snapping the dial if you force it to turn!

Your problem is in the Tap control probably (very likely) sludged up and a very difficult but not impossible problem to cure.
Have fun

scarecrow · Post by **scarecrow** » Thu Jan 13, 2011 7:00 pm

kiwi wrote:As has been mentioned plenty of referances to this problem in the forum.

Another thing to mention is it is not so much snapping the cable but snapping the dial if you force it to turn!

Your problem is in the Tap control probably (very likely) sludged up and a very difficult but not impossible problem to cure.
Have fun

I was wondering if it'd be possible to isolate the offending part of the cooling system and flush it with something to dissolve the gunk?

johnbird · Post by **johnbird** » Thu Jan 13, 2011 7:38 pm

ok i have been through ten pages and found one thread which appears to describe my problem.there is a picture-i like pictures-of the offending matrix and valve on a table.where / how do i gain access please? i would go and look but its dark and raining.do i go from the engine bay or the interior dash out job to reach it please?
i liked the idea of isolating the valve and chemically treating the blockage lots. i used cillit bang as a limescale remover followed by a thermostat out massive engine flush with new rad pipis to finiosh on the saab.cleaned out lots of crud from a system which had been standing for 17 years.

Dollywobbler · Post by **Dollywobbler** » Thu Jan 13, 2011 9:42 pm

It's up to the side of the driver's footwell. A right pain in the arse to get to - see if you can move it directly with your hand.

johnbird · Post by **johnbird** » Fri Jan 14, 2011 5:51 pm

is it going to be possible to access it from the cabin? will i need to remove the soft trim panel by my left leg? i have tomorrow morning set aside for this little job so the less voyage of discovery the better really. be excellent if a hand behind the panel could loosen it off well enough to live with as i have a plan to use household central heating descaler on the system.a step up from cillit bang i used on the saab.

kiwi · Post by **kiwi** » Fri Jan 14, 2011 9:43 pm

To gain easier access

Remove Drivers seat

Remove lower cowling/trim on steering column

That way you can lay on your back in the utmost of comfort and fiddle to your hearts content with the tap.

If your going to flush the tap and therfore heater matrix disconnect the two hoses from it in the engine bay bulkhead.

Also flush your cooling system at the same time to stop a reoccurance of said problems.

If above fails.......

You tried your best.