banging hw radiators

ED_45

thank you for your reply. the temp of the boiler is at 140
with 22 lbs. pressure once the thermostat is satisfied thought of "flashing " but the hi limit is definiteley working. the pump is a taco 110.

ED_45

dont know what to do

I have a hot water sytem with the original column type radiators that has been in place for 20 years. LAST SPRING THE RADIATORS STARTED BANGING when the thermostat called and the circulator activated for heat. But they didnt start banging until the radiators started to get from warm to hot. This condition continues after the themostat is satisfied and the pump is off. It is not unusual for the circulator to be off for as long as three hours and i still get a sound that can only be described as someone hitting the radiators with a hammer. My heating guy doesnt believe it's air, there's no gurgling sounds coming from the radiators. But they bang and bang loudly. Any one come across this before?

Mellowman

ed

the radiators will bang from a few things........ 1. is water so hot it becomes steam.... but after 3 hours are the radiators that hot???? 2. from expaintion but this just started.... what would have changed??? 3. broken valves rattling when the circulator runs but you said it is noisy with out the pump????????? If I had to guess it could be temp. and psi related...... too low of psi in the system and the boiler getting above 212 deg would keep the high points of the system seeing steam after the heat turned off. good place to start is temp. and preasure.