I have a hot water baseboard heating system 2 zones valves one zone is what the call a split zone it leaves the boiler in the basement I think 1 ins copper pipe goes to the end loops back to the boiler like in a u shape if you know what I mean the return is 3/4 copper the water seems hot going and coming but the house never seems to get very hot it works but not very well what could be wrong would it be that the zones are too long. Pump seems to work OK thanks for your help