Heater not working

[SandyB]

My 1998 A4 2.8 just has one problem - the heater used to work and then stopped.
If I feel the two pipes coming from the engine, the left is hot and the right is cold. Could it be the valve or the electrics or the controller, and how do I get to the valve to check?

[olds_kool]

is it blowing any air at all? if not motors probably gone (brushes worn out) you can get an o.e valeo motor or new brushes on ebay, fairly easy to to fit its behind glovebox, just make sure you get the right one if you have aircon