My other half's Ford Ka has started blowing out just hot air from the heater vents in the car, even when the control is set to it's coldest setting, and also with the air con switched on it makes no difference!
What could cause this, would it be a heater matrix type issue???
I've checked the water level to make sure it's not overheating and it was ok.

 

We had similar on a car at work, it turned out it was the control panel itself that was faulty.

 

I beleive that the hot cold bit is water tap controlled on these(but could be getting mixed up), so that is needing to be looked at, they often fail and are on the bulkhead easy to fix, or was it later fiesta's ?
tabetha

 

The heater control valves are known to play up. Ford bought a huge batch of faulty ones. You either need to replace it with a new, non-faulty one or drill a 3mm whole in it.

 

Make sure you get the latest level heater valve , there are 3 different types the last is the best ... the first is almost as good ..... but the middle one stay clear of .

It is correct that the control does go faulty , but only in about 5% of cases so go valve first