Radiator making loud water hamming noise and water sloshing sound

Alt0216

I have a one pipe steam heat and one radiator on the far end of 2nd floor has constant water sloshing sound when the heat is on. It sometimes also makes consecutive loud watering hamming sounds (very loud). The water hammer sound comes and goes, and I can hear it in the room and also the room directly below it on the 1st floor. The building is very old (50 years+) but the boiler has been replaced 5 or 6 years ago (located in the basement). The boiler pressure gauge is reading 2-3psi when running.

I have tried pitching the radiator up as show in the picture but that didn't seem to help much. I wonder if there's a problem with the connection between the pipe and the radiator or there are more problems? It does seem that this radiator is the only one making these noises.

KC_Jones

Is the valve open 100%?

Water sloshing and hammering is water laying where it doesn't belong. It could be the valve isn't fully open, there is a sag or incorrect slope in the piping leading up to the radiator. That radiator has been re-piped at some point, so I'd be looking at everything.

Alan (California Radiant) Forbes

Sweat x female 90 coming out of the floor? With the vent that high, the radiator was previously used on a hot water system. Just observations and may not have anything to do with the probelm at hand.

Alt0216

Thanks for all the comments. I had turned the valve to fully open, but I am not sure if there's a problem with the valve or not since it doesn't look like it moved much in fully open or closed position.

What would be some appropriate actions to perhaps solve this problem? Would I need have someone cut this joint and remake the piping to the radiator? Is there any way to remake this joint in a way that doesn't require opening the floor or wall? Thanks in advance.

Jamie Hall

I'm looking at that pipe coming out of the floor. Do you have any clue as to which way the runout under the floor approaches that pipe? Is there any hope you could raise the whole radiator? You have plenty of pitch on the radiator, and could lose some if needed.

What I'm thinking is that depending on where that runout is going and how it's piped there's a very good chance that it is trapping condensate, which would give you a really wicked hammer.

Alt0216

The pipe most likely has an L shape below as it needs to run horizontal with the floor since there's a room directly below. I suppose the current setup is like a "Z" - radiator horizontal pipe, vertical pipe, and then horizontal pipe again. But I am not sure which direction the horizontal pipe in the floor is pointing; it could be parallel or perpendicular to the radiator horizontal pipe on top. Does raising the whole radiator help? I was originally thinking the vertical pipe might be too long, but I am not familiar in this subject and that's just a guess.

Jamie Hall said:

I'm looking at that pipe coming out of the floor. Do you have any clue as to which way the runout under the floor approaches that pipe? Is there any hope you could raise the whole radiator? You have plenty of pitch on the radiator, and could lose some if needed.

What I'm thinking is that depending on where that runout is going and how it's piped there's a very good chance that it is trapping condensate, which would give you a really wicked hammer.

Jamie Hall

And not a bad guess at all.

If the pipe under the floor runs parallel to the radiator, then... if it goes under the radiator to somewhere, it almost has to be pitched the wrong way. Look at the angle of the vertical pipe. If it goes perpendicular to the radiator, it probably has no pitch at all. If it goes parallel to the radiator, but in the opposite direction, it may be pitched adequately.

In any case, it won't hurt to raise the radiator at the valve end -- if you can. Leave some slope on the radiator, though -- but it doesn't need to be as much as you have now.

Not saying that that will work... but it's worth a try.

ethicalpaul

It's already been raised 2.25" on the valve end looks like

bburd

Off-topic, I know, but how well does that room heat? With the air vent in the upper position intended for hot water systems, you are probably getting no more than 50% of the steam rating of that radiator.

If the room heats well, I'd leave it alone. If not, there should be a boss further down on that side of the radiator where the vent should be installed for steam heat.

EBEBRATT-Ed

The valve could be your problem.

@Gordo has a U tube video about the pitfalls of a straight globe valve on a radiator that you might want to peak at on U tube. Some designs don't allow the water to drain. You could remove the valve and hook it up without the valve and see how it works.

Alt0216

Thanks for pointing it out, the room is indeed not heated very well. It is on the far end and I always assumed that was the issue. I will switch the location of the vent.

bburd said:

Off-topic, I know, but how well does that room heat? With the air vent in the upper position intended for hot water systems, you are probably getting no more than 50% of the steam rating of that radiator.

If the room heats well, I'd leave it alone. If not, there should be a boss further down on that side of the radiator where the vent should be installed for steam heat.

Alt0216

Thanks for the info, I will look into this and maybe get a new valve.

EBEBRATT-Ed said:

The valve could be your problem.

@Gordo has a U tube video about the pitfalls of a straight globe valve on a radiator that you might want to peak at on U tube. Some designs don't allow the water to drain. You could remove the valve and hook it up without the valve and see how it works.

KC_Jones

Alt0216 said:

Thanks for pointing it out, the room is indeed not heated very well. It is on the far end and I always assumed that was the issue. I will switch the location of the vent.

bburd said:

Off-topic, I know, but how well does that room heat? With the air vent in the upper position intended for hot water systems, you are probably getting no more than 50% of the steam rating of that radiator.

If the room heats well, I'd leave it alone. If not, there should be a boss further down on that side of the radiator where the vent should be installed for steam heat.

To be clear, the vent is on the correct end of the radiator, it's just mounted in the location that an air bleeder would be in for a hot water system. Steam vents are typically mounted lower to ensure even steam distribution, especially when the radiators are top connected.

If you look at the end of that radiator you should see a boss that would get drilled and tapped for the vent about 2/3 down the end from the top.

Alt0216

KC_Jones said:

Alt0216 said:

Thanks for pointing it out, the room is indeed not heated very well. It is on the far end and I always assumed that was the issue. I will switch the location of the vent.

bburd said:

Off-topic, I know, but how well does that room heat? With the air vent in the upper position intended for hot water systems, you are probably getting no more than 50% of the steam rating of that radiator.

If the room heats well, I'd leave it alone. If not, there should be a boss further down on that side of the radiator where the vent should be installed for steam heat.

To be clear, the vent is on the correct end of the radiator, it's just mounted in the location that an air bleeder would be in for a hot water system. Steam vents are typically mounted lower to ensure even steam distribution, especially when the radiators are top connected.

If you look at the end of that radiator you should see a boss that would get drilled and tapped for the vent about 2/3 down the end from the top.

Thanks for clarifying! Is the location I circled in the picture where I should tap into and mount the air vent instead? Can I seal the original location on top using a 1/8" bolt? I think the air vent is 1/8"?

bburd

Yes, that's the correct location. And you may not have to drill and tap it if you can get that plug out.

Alt0216

I tried closing the on/off valve fully today and then also blocking the air vent as well, but I am still hearing constant water running sound in the pipe and less often but some hammering. Would that mean that this is a problem with the piping underneath?

STEAMFITTER597

Now you’re on it!  Find that pipe below floor. Radiator takeoff tee should be on a 45 slant. Allows condensate to hug the pipe wall. Drips become Missile hammers.  Follow the pipe. Near the end it may have an end of main vent. If plugged radiator is trying to vent branch. Watch the level of the main.  It must pitch. Watch for sags. Mentally be the condensate. How does get home.  Steam rides top of pipe, condensate runs like a river in the bottom.  

Just an idea. 

ethicalpaul

Keep in mind that relocating the vent is fine, but is not going to solve your problem

bburd

Relocating the air vent will solve the under heating problem, but not the noise problem.

And regarding closing the vent hole near the top of the radiator, no you cannot use a bolt. It needs to be a pipe plug, which has a tapered rather than a straight thread.