Well luke warm actually.
I have a 97 300tdi. Up until a few weeks ago it was lovely and toastie. Heater would be warm within a mile or thereabouts. Then all of a sudden one day I just got cold air. I have bled the system for airlocks, changed thermostat, flushed it, new water pump (it needed that old one was squeaking and also noticed a leak at the pump) new temp sender. Engine now reache optimum temp reasoanbly quickly but the heater air is barely warm? Any thoughts especially as it is cold at the moment?