There are three possibilities. 1. You have an airlock. Do you have to keep on topping up with water? If so you have an airlock, which means you willl have to run the engine, wait for the water level to drop in the radiator chamber and top up again with heaters on full blast to blow the airlock out. Keep doing this until you feel hot air coming through. 2. There are a system of interlocking cables between the heater matrix pod and the controllers on the dashboard. The one between the hot air dial has either broke or popped off from the duct door that opens and shuts depending on if you want hot air to flow into the cab. Three. The heater matrix itself is blocked with crap. In that case its a new matrix. Are there any fuses which could be responsible? Thats it. I can think of no other possibilties.
col, December 2010
