Katrina Baker
: We have hot-water-heat with a radiator in each room of our first floor. Almost every time the heat kicks on, the pipes in or near every radiator start banging. Sometimes this happens right away, sometimes not for a few minutes after the furnace kicks in. We have tried bleeding the valves, but water comes out right away — no air first. Is there anything we can do?If a thermostatic radiator valve causes a water hammer type sound, it indicates the flow is not in accordance with the proper direction of flow as shown on the valve-see the arrow. Stated another way, the vavle is in backwards and the supply pipe is on the side of the radiator that everyone thinks is the return. This can be checked by measuring the temperature at supply and return, supply must always be hottest.
