No hot air, most of the time. All vents, controls working, in and out hot.

[Petedavies]

I had this fault on mine, it turned out to be the two coolant hoses that go into the heater matric through the bulk head had a couple of small splits in them causing air locks constantly. The hoses can be seen to the left of the battery when you open the bonnet. I was fed up of doing repairs on my car so I wrapped insolation tape around the offending area, ran a hose through the heater matrix, 2 months later still nice and toasty warm thanks to a quick fix!