1.4 tdi heater not working

[hunter]

Hello All,
The heater in my Tdi with air con seems to be fine when first turned on from cold then as the temperature on the gauge rises it starts to blow cold.
The gauge reaches 90 and sits there but the heater blows hot for a while then cold then hot then cold.
Any thoughts ?
Ian

 

[depronman]

sticking / worn heat control flap unit
try exercising it by going from hot to cold and back to hot 20 or 30 times.
If this does not fix it then its a new flap unit (bitch to change unless you have ultra small hands)
@timmus is the expert (he will love me for this)

Paul