My interior heater in my ford KA does not work .What could the problem be

Dave, November 2005

I fixed my heater today following Danny B's instructions as above. It took me nearly two hours and Im quite a practical bloke. I didnt need WD40, in fact I couldnt see how it would help, I just squeezed the clips with pliars and slid them down the pipes then released each pipe using a flat blade screw driver to get them started. They pushed onto the new valve with no problem and no grease. There was no sign of clips braking. Ive noticed that a symptom of this fault is it takes longer and longer for the heater to come on untill the solenoid eventually siezes up in one position, this is a very gradual process so it may go unnoticed untill full failure on either hot or cold. If you turn on the ignition wihout starting the engine and turn the heater fan to position 1 then operate the heater control back and forth a new valve will make a dull clonking noise, the siezed valve makes no noise of course. My valve cost me 30 quid. A bit of coolant was lost taking the top up tank down to minimum, I topped it up to max with a bit of tap water.

Daypr0, March 2009

Common problem on KAs is a sticking heater control valve. Look under bonnet, central behind engine on bulkhead for the two coolant hoses that connect to it. Its electrically operated and can jam after a period of non use i.e set on cold all summer! A new valve is £25-£35 from a Ford dealer (they usually have in stock). It's not a big job to replace just a bit fiddly. Can be done from under bonnet in under an hour. Remove wipers, shorter one goes on driver's side. Remove scuttle trim screws (under plugs) and scuttle trim halves. Locate and remove screws that hold bulkhead trim in place. Remove passenger side trim. Not position of any harness clips and pipes. Move driver's side trim out of the way. Valve should now be accessible. Release hose clips with pliers/molegrips and slide off hoses. If stubborn, squirt some WD40 under pipe/valve joints, some coolant will be lost. Disconnect electrical connector. Valve hooks onto bulkhead. Fit hoses as they came off, use a small amount of copper grease on valve unions to ease this. Clips can be reused but if they are weak or break, replace with screw hose clips. Hook valve onto bulkhead. Re-connect power cable. Good chance now to clean all the accumulated muck from bulkhead area, the base of the windscreen and lube the wiper linkages. Replace trim in reverse order noting any cable/pipe routing and trim around valv inlet pipes. Remember wipers are side specific.
Hope this helps.

Danny B, November 2006