My heaters don't work on my streetka , when I've been driving for about 30mins I can feel a little bit off heat getting blown throu the heaters but nothing much even when the heaters are all switched off . Could it be the heater control valve and are the heaters all the same on the ka's

same as the fiestas just below the bulk head.

this will give you an idea

Do it sound like the heater control valve or something else

It does sound like the HCV. If it was the thermostat it would warm up more when stationary and cool down when in motion. HCV's are such a common problem it is always going to be the most likely culprit.

you can buy them from auto factors or off ebay .

http://www.ebay.co.uk/itm/Ford-Fiesta-KA-Puma-NEW-HEATER-CONTROL-VALVE-/181012700721

Thank you will be ordering one tomorrow off ebay

it may also be this part thats playing up but its only gone when there is no blowers working apart from setting 4 from memory.

this part is located under the passengers footwell by 1 screw under glove compartment

http://www.ebay.co.uk/itm/like/190851067725?hlpht=true&ops=true&viphx=1&lpid=95&device=c&adtype=pla&crdt=0&ff3=1&ff11=ICEP3.0.0&ff12=67&ff13=80&ff14=95&ff19=0

here is ford link for the part and prices remember you got to add vat to the prices

http://www.fordpartsuk.com/shop/ford_fiesta_heater_resistor_f_1104100_c_278.htm

i had to change my heater control valve a few months back when mine had gone though i only had cold air. hope that be of some help.