clanking and gurgling steam pipes

toraziyal

We have a one-pipe steam system. Recently due to the freezing temperatures in the northeast, we had some bathroom pipes burst in our first-floor bathroom.

That said, we turned off the water to the entire house and turned off the boiler. We had to turn the main water on and off to troubleshoot and isolate the location of the burst pipe. Luckily we have so many cutoffs we were able to isolate the water going to that bathroom.

Once we did that, we turned the main water back on as well as the boiler. The water in the boiler looked low, so we added some. (Note: that there is also an auto feeder on the boiler).

Once the boiler started up again, there was lots of clanking with some gurgling (we did not have this earlier in the season). I think we've isolated a couple of the first-floor radiators as the problematic ones. To me, it seems like we overfilled the boiler and now the excess water is not draining back properly.

The other bit I am worried about is that turning the main water on and off several types may have changed the pressure inside the boiler. Is that possible?

Anyway, my thoughts are that we need to drain a little bit of water from the boiler and then pitch the troublesome radiators a little more so that they drain properly.

Any advice appreciated!

Update: see below. we got it sorted.

ethicalpaul

How full did you fill the boiler?

Why did you shut off the boiler during your water pipe troubleshooting I wonder? (not that it was harmful)

You didn't affect the "pressure in the boiler". There is only pressure when steam is being produced. Otherwise, it's atmospheric pressure in there about 2 minutes after the burners stop.

If you have gurgling sounds along with clanking it is likely that the clanking (water hammer) is being caused by water being pushed into your steam pipes (which is normally caused by bad near-boiler piping but can certainly be caused by an overfilled boiler) and may not be caused by faulty pipe pitch.

Get the water level where it should be (do you know where that is?) and then see how it does.

Long Beach Ed

If the problem has gone away, it was simply caused by the radiators being very cold when you restarted the boiler. They would produce more condensate then, which might have unusual trouble draining back to the boiler. That would cause the problems you describe until the building heats up.

Sully1266

You may have overfilled boiler when you fed it manually, look at the site glass if it looks empty a good trick to use is put your hand behind it and look through glass if your fingers looked magnified the glass is full even though it looks empty. Being you stated system was working fine before the freeze I would think you don’t have piping or near boiler issues. It’s always better to eliminate simple quick fixes before you start to think about big piping issues. I would drain a few buckets of water let feeder refill for you then check level in glass to see where it’s bringing you. 

toraziyal

We got it sorted.

We ended up draining a bit of water from the boiler until the sight glass was about 1/2 to 2/3 full. It was almost near the top of the cold boiler.

No more gurgling or clanking.

The reason we added the water originally was that it would drop to the base of the sight glass once the boiler was good and hot and the radiators were all hot.

One other thing we noticed was surging in the sight glass when the boiler was at the beginning of the cycle as well. By the end of the cycle, the water is near the bottom of the sight glass still surging.

We talked to our plumber and he said we probably need to skim the boiler. That will be the next thing we accomplish over the next few days.

KC_Jones

Is this a new boiler or any recent piping changes?  Skimming is needed when a boiler is new or it has some piping done to it.  This is to remove the oils causing surging.

Surging can also be caused by poor boiler piping.

toraziyal

It’s an older boiler. There’s loads of weird piping around the boiler because there’s an on demand hot water heater and an expansion tank attached to the boiler. This was all put in by the previous owner who was a plumber. Probably worth having my plumber take a look at it.

Mad Dog_2

Now you got us curious ToraziyL! How's about some photos of these strange pipes?   Mad Dog

EBEBRATT-Ed

How often are you adding water? Sounds like you are losing water as well

toraziyal

Here’s what it looks like.The only thing uncomplicated is the first photo!

Waher

The pig tail looks more pig iron than pig tail at this point and should be replaced.

Mad Dog_2

Pics are kinda dark but
1) Replace that black steel.pigtail with brass and rod out tapping in to boiler
.2) pigtail steam.siphon is positioned the wrong wsy.if that's a Mercury P tool Looks like it. 3) not carry about that header. Mad Dog.