normal running temp thats slightly high. no hot air could be air lock. has it got a thermostat in it if it has look for a bleed nipple around the thermastat housing some have them some dont run the engine turn the heaters over to hot leave it set on cold it wont circulate after its circulated properly it doesnt matter. no thermostat no hot air. im assuming you no you have to undo the bleed nipple to release the air untill you only got water coming out of the nipple