Does anyone know if this is a serviceable item ?

 

The heater appears to have a mind of its own and won't adjust properly - some have said it is likely to be the heater flaps - 

 

Where are they located ? Is there a DIY guide on how to resolve/replace.

 

cheers

You can perform a basic setting using vcds which could resolve the problem. What is the nature off the problem.

On my car it is either hot or cold no in between I have managed to get a new control panel off eBay and will have the pleasure off changing that next weekend. Failing that there is a flap motor which controls the temperature flap.

Probably not the answer you were hoping for as it's not a quick fix

I have complete heater box if needed

VAG car heater flap motors giving problems, hum, that has been happening since VAG started using them, always annoying and mainly reasonable difficult to reach to remove/replace, and usually due to gumming up of the positional feedback track. You might look for some youtube tutorials on removing, cleaning and replacing flap motors.