late 80's boiler and c/h system. Recently the pump stops working after about half an hour and gets very hot as well as the pipework from the boiler to the pump.. also I have noticed that the radiators on the end of the run are not warming up properly if run on c/h and h/w. I am assuming the pump is weak/sha**ed. just want to get an idea, i know the plumbers going to say i need a new c/h system.