heating pipe near boiler hammering

Juniorsquan

hi..I get a lot of hammering sound coming from this section of the steam pipe (see attached photo). This is a one pipe heat steam system by the way. the return line has an 90 angle that is facing up, even though the return line has a pitch towards the boiler, i think that 90 angle facing up is preventing the water from flowing towards the boiler and that's causing the hammering sound....Please advise if my theory is correct.

Thanks,

Jamie Hall

One pipe... but with return lines to the boiler? I'm confused...

However. If there is a line in which water can collect -- that is, pitched or in your case with an elbow --and not drain freely to the boiler or to a wet return, it's going to hammer. The only way to correct it is to correct the piping so that there is nowhere for the water to become trapped.

Fred

That piping doesn't make sense from what little we can see. Post a few more pictures if you can give us a long shot of that pitched pipe that runs from the up-turned elbow. None of that piping looks new so has it always been hammering?

Abracadabra

Looks to me like someone moved the return to increase headroom in that basement. If that is indeed the return after what looks like a runout to a radiator, then it needs to be repiped to allows condensate to flow back to the boiler.

Juniorsquan

I just moved to this house, so I don't know if the previous owner had the same problem..I was thinking exactly the same as Abracadabra, I think someone just moved up the pipe to leave more headroom in the basement. I believe water would get accumulated on that 90 angle causing the hammering sound. I just want to make sure before hiring a plumber to removed that return line. I posted another photo with some red line drawings, hope it helps..Sorry my adobe expired so I had to use Microsoft paint. Thanks for the comments.

vaporvac

could you post a pic of a typical radiator?

Fred

Juniorsquan said:

I just moved to this house, so I don't know if the previous owner had the same problem..I was thinking exactly the same as Abracadabra, I think someone just moved up the pipe to leave more headroom in the basement. I believe water would get accumulated on that 90 angle causing the hammering sound. I just want to make sure before hiring a plumber to removed that return line. I posted another photo with some red line drawings, hope it helps..Sorry my adobe expired so I had to use Microsoft paint. Thanks for the comments.

Yes, that pipe needs to be repiped so that the elbow drops below the Main (Pipe that feeds the radiators). You don't want to remove that pipe as it needs to be there to carry return water from the end of that main. When it is dropped below the main, make sure it is pitched towards the boiler/wet return.

KC_Jones

If this is a one pipe system you should get some provision installed for main venting in that same location (since you are getting the piping worked on). I don't see any main vents in those pictures and that is a problem, again if this is a one pipe system. Pics of the rads will help determine that also.

Abracadabra

Juniorsquan said:

I just moved to this house, so I don't know if the previous owner had the same problem..I was thinking exactly the same as Abracadabra, I think someone just moved up the pipe to leave more headroom in the basement. I believe water would get accumulated on that 90 angle causing the hammering sound. I just want to make sure before hiring a plumber to removed that return line. I posted another photo with some red line drawings, hope it helps..Sorry my adobe expired so I had to use Microsoft paint. Thanks for the comments.

Does the radiator attached to that last runout before the main turns up even heat? I'd expect it's vent to spit quite a bit of water.

Juniorsquan

Yes Abracadabra, occasionally that radiator above that last run out spits some water.

Kc_jones- I posted a picture of the main vents recently replaced with two new Gordon's # 2. Also raised them up 6 inches from the elbow as suggested on previous discussions.

vaporvac-- photos attached of downstairs and upstairs radiators

Correct Fred, I meant to say repiped instead of removed.

The problem I'm having is just in the right side of the run from the boiler. lets call right side ( the one with the problem) On the left side run of the house everything is fine ( photos attached).


Sorry for the bad photos , but there's not enough space down in the basement to get the entire overview.

Fred

In your second Picture, what you have labeled as a "Wet Return" is actually a Dry return. If it is above the boiler water line, it is "Dry Return" when it drops below the boiler water line, it becomes a "Wet Return".
Also, those new Gorton #2's look great. Do you have Gortons on both the Right and Left Mains? Both need vents on them at the end of the Main so that the steam flow is balanced between the mains.

Juniorsquan

Fred- I installed two Gorton's # 2 one for the right side and one for the left side. I'm confused now... the two gorton's # 2 are installed on the 1 1/2 pipe, were they supposed to be installed on the 2" instead.

Fred

Juniorsquan said:

Fred- I installed two Gorton's # 2 one for the right side and one for the left side. I'm confused now... the two gorton's # 2 are installed on the 1 1/2 pipe, were they supposed to be installed on the 2" instead.

The best place for them is at the end of the " Main, after the last radiator run-out. That way they can vent the volume of air in the mains and not have to also vent the air in the 1-1/2" returns. Returns don't have to be vented. It is OK if you have no other place to put the vents but venting the Mains, on a 1 pipe system is the goal.

Abracadabra

After looking at all your pics, you need to have someone properly pitch that pipe. Is there a union on it somewhere? I can't see one.

Juniorsquan

Fred--gotcha! well it looks like I only have vents installed for each dry return mains and for what I can see I don't have any vents on the Mains. Thanks for the tip, I will be hiring someone to look at the pipes.


Abracadabra - I will be hiring someone to look at it.. i don't see a union anywhere on that pipe, its just goes from elbow to elbow.


Thanks!

Jamie Hall

Fred said:

Juniorsquan said:

Fred- I installed two Gorton's # 2 one for the right side and one for the left side. I'm confused now... the two gorton's # 2 are installed on the 1 1/2 pipe, were they supposed to be installed on the 2" instead.

The best place for them is at the end of the " Main, after the last radiator run-out. That way they can vent the volume of air in the mains and not have to also vent the air in the 1-1/2" returns. Returns don't have to be vented. It is OK if you have no other place to put the vents but venting the Mains, on a 1 pipe system is the goal.

If it is a one pipe system, Fred, you are correct -- the dry returns don't have to be vented.

But

If it is a two pipe system, the dry returns are venting the radiators, and they MUST be vented. The mains may be vented in some -- but not all -- two pipe systems. In some they must NOT be vented, but connected to the dry returns through crossover traps.

Bio

Hope you get a true steam pro, the second picture from your first post shows 2" main with elbow going up above the main and reducing to 11/4" and returning to the boiler, it should be turning down under the 2" main with a pitch returning to the boiler, you have to pitch high from boiler so when steam condenses has a down pitched flow to return to the boiler, if not when steam and condensate meet it will hammer, you should have something like in the shower picture, hope you get the idea, where are you located, we may know someone in your area

nicholas bonham-carter

Of course it's true that the mains can be vented, after the last radiator, and this is the only choice for a counter-flow system. I prefer the main venting to take place on the dry returns, next to the boiler. For one thing, it places the main vents all in the same area, so they can be observed as they do their job, and it does not leave a slug of air in the dry returns, which may expand with heat, and become a wildcard.--NBC