I have just had a new water hose fitted by my local ford garage , the other one obviously burst, but now my heater is not blowing out hot air ? I checked the hoses this morning after a decent run and the hoses that go into the engine block,as you look at it from the front ,the left hand hose which goes to the bottom of the radiator is stone cold and the other one with the swirl pot in the line is roasting, as are all the others. is this normal ?