Can anyone help I have an old 1998 1.3i fiesta the heaters won't work the heater fan works but won't heat up ,I just replaced the thermostat hoping it was that but it's not fixed the fault also noticed the gauge sits on the low side although the engine is at temperature any ideas what it could be 

Sounds like it may need a new heater matrix


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The 2 rubber hoses that go into the bulk head are hot to ,is it much of a job replacing the matrix thanks 

I think it can be not had to do it before but I think you have to strip the dash. Don't hold me to it though I could be wrong


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Could it be heater control valve ?

Maybe yes. Is it damp in the front foot well


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No damp on the floor not noticed any water loss

That's a good sign then maybe check cable for the controls. Maybe come off or snapped


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I looked beyond the heater control and it's a circuit board not cable for hot and cold ,so I'm assuming that controls the heater control valves on The matrix pipes is there a way i can work out what's causing the problem

Without a wiring diagram I couldn't really say sorry mate


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It'll almost certainly be the heater control valve. They are pretty much a consumable item on your mark Fiesta.

There is a heater resistor in mine. They blow, if there is an issue with heater motor. Unfortunately, official Ford part only. No 3rd party support. Get one on eBay/Breakers. Mine are £60.00 each. Not nice if they keep blowing.

A failed resistor would stop the fan from working (but that's been confirmed as okay).

The heater control valve is too common a problem to avoid ruling out first.