Steam Heat Radiator Banging

khills2

I have a steam heat baseboard radiator that is banging when heating up. On top of the banging, the air vent (it’s new, I just changed hoping it would fix the banging) gurgles and spits out water during the heating process while the radiator bangs. The radiator has two air vents, the one further from the steam valve is the one that spits water. It sounds like water is moving through the radiator, too. Once the radiator is hot, the sounds stop. 

Before calling a plumber I want to ask this forum for any advice on how to tackle the issue is appreciated. 

neilc

1 pipe rad, correct ?
post pictures of what you just described,
the rad should be pitched back to the supply,
put a very slow vent at that far end,
what is your pressure at the boiler?
pictures there also,

khills2

1 pipe rad. I have a “5” air vent on both ends. Should they be different? 

I believe pressure is at 3? Attached are two pics. 

neilc

like to see that rad with the covers off,
the fins are to the right, correct?
and there's 2 vents there?
oh to see , , ,
the far vent, that end of the fintube, it's higher than the valve end, correct?

the Ptrol is set too high, dial it down to the 0.5, or lower, don't dial past resistance,
inside the cover, the differential wheel should be set to 1,

has the pigtail been serviced? free and clear breathing back to the boiler?

what pressure do you see on the gage as it's running hard?

khills2

The fins are to the left and right of shut off valve. To the right (according to image) is a small amount though. I just put a block of wood under a part of the rad to make it unleveled (downslope to the valve). 

The pressure gauge does not work, never noticed until I looked now. Stays at 0. I had it serviced prior to winter, guess the servicer was not that good at their job. If they didnt say it was not working. 

You recommend lowering that cutin line from 3 to 0.5? 

neilc

"I just put a block of wood under", , , as in just now?
now what about the left end?, both ends need pitch to drain back to , , , that "Center" valve?

some 0-30 gages have a hard time registering,
others have blocked pigtails,
and if your pigtail isn't clear, then the Ptrol can't see what the boiler is doing either,

and Yes, absolutely, lower the Ptrol,
steam shouldn't run above 2psi,
1.5 is better,
set the front cut-in scale to 0.5, and the differential cutout to 1 for a 1.5 cutout,

khills2

Yes, I put a block of wood under a part of the pipe towards the right end of the image to give it a downward pitch towards the valve. The left end seems to be pitched downward towards the valve. 

After I added the block of wood the pipe banging stopped. So as of now, it mustve been the pitch of the radiator. 

I will adjust the ptrol. To adjust the cutout, do I open that box to find the dial for the cutout?

khills2

neilc

much better on the Ptrol,
now unscrew the gage by the flats on its back,
and see if you can blow thru that pigtail,

neilc

sightglass looks ichey dirty,
better picture there,
what have you got for a skim port ?

khills2

I’ll get to the pigtail next weekend. Might have someone come by to help out with it. 

What is a skim port? 

neilc

you should look at, or google and download, your boiler manual,
it's a capped pipe nipple, higher on the boiler side, where you float the oily ickey water off the surface of your boiler water, (not a low down drain),
clean water boils easier,
your dirty sightglass and dirty bouncing water inside is the tell tale,
your installer or maintenance man/plan should have skimmed to clear all oils when boiler was installed,