Steam pipes banging for the first time

Jason_44

I'm having all sorts of problems with my one-pipe steam system (oil-fired, Beckett burner, Utica boiler about 10 years old).

The system has worked fine for years, but a couple of things changed this past summer and now I've got banging all over the place.

1. I had 2 radiators relocated, each only a few feet from where they were before.

2. I insulated the entire house this past summer (blown-in cellulose in the walls, Icynene foam in the attic), which is causing the boiler to come on less often and it doesn't run for long periods like it used to.

My theory for the boiler not running as much or as long is either because of the insulation (which was the whole point -- to save on fuel costs), or the fact that one of the radiators that got moved is now closer to the thermostat.

The pipes running to the new radiators are not insulated (yet). All radiators, including the newly-relocated ones, appear to have good pitch and all pipes have good pitch.

All air-vents are brand new and work fine, including the main vent. They hiss and air is escaping like it's supposed to.

One of the radiators farthest away from the boiler wasn't heating all the way across. I removed the vent while the boiler was firing. No air came out, then all of a sudden water started spurting out (not steam, but water). That leads me to believe there's water sitting in the radiator or in another part of the system. The problem with this radiator seems to only be intermittent.

Any ideas? What's causing all the banging? Pictures are attached.

nicholas bonham-carter

squirting rad

is the radiator valve all the way open. sometimes the disk on the bottom of the stem can fall off and block the opening like a check valve.does that rad bang?
sometimes over pressurised systems can bang-is yours under 1 psi?if you know exactly which section of pipe hammers you could check for a partial obstruction.hard to see from your pix but the water in the glass looks dirty, might be time for a cleaning.--nbc

Jason_44

Pressuretrol is on its lowest setting. Shut-off to that radiator is fully open. Water occasionally shoots out of the air-vent (which is a new Vent-Rite that I just installed yesterday). Radiator is shimmed toward the supply/return pipe. I tried blowing through the vent to confirm that it's working.

Could I have a wet steam problem? If so, how do I fix? Can dirty water lead to wet steam?

Jason

David Nadle

check the radiator pitch

Sounds like the condensate is not draining out of the radiator. The radiator should be pitched towards the pipe. put a level on it and shim the opposite feet until you get the right pitch.

Jason_44

Radiator is shimmed and pitched correctly.

The banging is occurring in the pipes throughout the basement and is very random. Hard to locate exactly where the problem is.

kpc_40

when the work....

was done... did they clean the water side of the boiler. All that new pipe has oil on the inside of it. System should be skimmed, flushed andcleaned very well.

ps.. that thermaflow gizmo is not piped properly either. If the near boiler piping was done right it sould not be needed...

Steamhead (in transit)

Start with proper near-boiler piping

that thing is not piped correctly. I'd use two 2-inch risers to a 3-inch drop header feeding separate take-offs for each steam main. I bet the present piping is producing wet steam even with that Thermoflo separator.

How long is each steam main and what pipe size? That Vent-Rite main vent just may be too small.......

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Jason_44

It's been piped this way since the house was built in 1939. The "dead men" who ran the piping are long gone. The system has worked fine for many years, however I'm pretty sure the steam has been a little wet, because I'm constantly replacing plugged-up air vents.

All I care about is how to get rid of the current banging issues. My guess (and I'm not an HVAC contractor by the way) is that there's cutting oil that got into the water and it needs to be skimmed. I'm just not sure how to do that. I don't want to call my oil company techs. They charged me enough already just to relocate the rads. I would've done it myself, but pipe-threading is about the only plumbing job I'm not set up for.

JW

Steamhead (in transit)

You say

"It's been piped this way since the house was built in 1939"

That's part of the problem. Boilers were different in 1939, and you could get away with a lot more than you can now. Look at the boiler's installation instructions and you will see some very specific minimum pipe sizes and dimensions. These must be followed for trouble-free operation.

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Jason_44

I'm starting to think you're right about that. I think it's a safe bet that I've always had "wet" steam, given that the radiators hiss like mad all the time and I usually have to replace the air vents every year or two because they get so gunked up.

Somebody suggested a larger main vent. What's the biggest one I can get? Will this help with the wet steam problem? Or just the hissing?