Banging radiators - Again I know it's been beat to death...

faster340

I have one radiator fiercely bangs. It's a one pipe steam system. The radiators that don't bang I hear the valves hissing when it's making heat. The radiator that does bang I don't hear the valve hissing. Could this be a bad valve causing the banging because it can't release pressure? The radiator has been tilted towards the valve numerous times and at numerous heights.



Thanks.

BobC

Piping

Have you tried swapping air vents with another radiator?



Make sure the pipes that feed this radiator are sloped properly so water can drain back to the steam main and make sure the slope on the steam main is ok.



If none of that works try removing the vent on the radiator and see if any air is coming out of the vent tapping. Do this when the boiler firs comes on and the system is not steam hot.

Put that air vent back on when the test is done.



If you get no air coming out as the system begins to produce steam your input radiator valve might be stuck closed, not letting any steam in. I don't see why that would cause hammering without any trapped water in the main or at the start of the radiator feed pipe where it comes off the main.



Bob

faster340

suggestions

Thanks. I will look into your suggestions...

jpf321

quite likely...

the floor valve is not fully open (even if fully turned open)..you may need to take it apart or replace with an new one or elbow..it could also me that your supply pooping is too small.



certainly easy test its to swap air vents between good and bad rads...more involved to working on the supply end.

faster340

quite likely...

it's open all the way. I will swap air vents and see how that goes. Thanks.