Help please! Drastic change in glass gauge level from off to on

greg556

Hi--

We've installed a new boiler for a home (1300 sq. ft.). The boiler is a New Yorker CGS50. The water is filled very high when the boiler is not running. (80% or more of the gauge.) When the boiler starts firing, the water level very quickly drops all the way down to the bottom nut of the glass. (It takes under three minutes for the water to level to fall.) The level then stays at that level, right at the top of the nut, until the boiler turns off. The low water cut off is never engaged. When the boiler turns off, the condensate quickly returns to the boiler (again a couple minutes) and the level in the gauge goes back to 80%.

What is wrong? Is it a problem, or is this within normal operating limits? What do we do to fix it? I am attaching two pictures, high water and low; I can also send you a 4 minute video from when the boiler starts until the water disappears. Thank you!

ethicalpaul

Your problem is possibly bad near-boiler piping which is allowing the boiler to push out gallons of water into your steam mains which is a Bad Thing™.

You can send pictures of your boiler and its near piping from about 10 feet away from all different angles and we can verify that for you.

Sorry to bear bad news but a possible root cause is that your installer failed to follow the simple directions in the installation manual.

If you're lucky (and the gunk visible in your gauge glass points to this possibility), the boiler just needs to be skimmed, which also your installer should have done. Skimming removes oils from the surface of the water which also cause this "surging" behavior.

Finally, what did your installer say when you asked him about this behavior?

Jamie Hall

Definitely not normal. An inch or even two, quite likely. That much? No. And I'm afraid I agree with @ethicalpaul 's initial thoughts.

greg556

Thank you, both of you. Here are several pictures. I am fairly confident the piping was done properly, but I will leave it to your judgment. The skimming he definitely did not do. He saw the gunk in the glass and kind of skedaddled.

The installer's immediate reaction was that there is not enough capacity and the boiler needs a small reservoir tank. That sounds reasonable, but I'm not sure, because the water level drops so quickly, I think there may be some other problem causing the behavior. He has called some one else for their opinion, and now they want to install an automatic feeder. I *know* that isn't right, so we seem to be getting further away from actually problem-solving.

It's a very old house that we just bought (in November), so we presume anything and everything might be wrong. Three of the radiators work well, one not at all and one is very slow. There is severe hammering. I've put new vents on all of them, but even with the slow one on 6 and the rest on 1, it's still slow to heat.

Thank you for your help with this! Here are the pictures:

JUGHNE

IMO, the new boiler piping looks pretty good.

However, you have a double header there with 2 equalizers, one going normally into the top of the Hartford Loop and the old one going into the return below the HL elbow.

IDK where your water goes that quickly.
In 3 minutes it would not boil off to where you need a reservoir tank, IMO.
That is needed for slow return water and you have not had enough boil time to send out that much water.

Could you post more pictures showing more detail of the older steam main, a couple angles showing floor to ceiling from both sides.

What pressure is this adjusted to and does any show on the gauge as it fires?

Jamie Hall

As @JUGHNE says, the boiler piping isn't bad at all. Much better than some.

And the suggestion of a reservoir tank is not good -- that won't help. And an automatic feeder certainly won't help.

However, you do have one problem which may be a good part of the whole problem: the hammering. That indicates that water is trapped in the steam feed pipes, probably in a number of places. You need to go through the whole system, inch by inch, and check that all the piping is pitched properly to drain quickly back to the boiler. In an older house it is not at all uncommon for the pitch to be too little -- or even reversed -- and sags to develop. Older places tend to settle...

So get after that one.

JUGHNE

Are there any return pipes connected to the lower part of the boiler.
Those that would be on or under the floor or dropping down from the ceiling.
Not connected to the steam main.

This may be a counter flow steam main??

mattmia2

Is that 3 minutes after it is already hot? I'm not sure I see a fitting to skim from as it is currently installed, but judging from the amount of dope on the outside of the pipes it definitely needs to be skimmed if it hasn't been.

clammy

Looks like you have a counter flow mains and the end of which is your condensate drip . Your installer did pipe your main well from over head nice way to feed a counter flow systems .Your issue may be no main vents at the end and not enough vents on your radiators w running to high a pressure . Did your installer do a edr on your radiators to ensure it’s not oversized ? Over sized boilers and counter flow systems never seem to get along to well .What is your pressuretroll set at , should be as low as possible .5 cut in 1.5 it out .it’s usually better to operate a counter flow system w a vaporstat ,you should get an 0-3 psi gauge to verify your operating pressure and try to keep the pressure as low as possible . Also did your installer flush and skim the boiler to ensure that all manufacturing oils where removed . I also would not jump to the conclusion that you need a reservoir tank , usually it is when the boiler runs for at least 1/2 hr to 45 minutes and the radiators are not even completely warm yet and your off on low water . In your case this does not sound like the issue being water leaving the boiler with in a few minutes of steaming . I would start w flushing the boiler and re filling and skimming till no more surging and check for main vents and the condition of the radiator vents . On a counter flow system w out main vents your radiator vents work double over time so don’t think that just because there 4 years old that they are not shot most likely are espically if non of your piping is insulated which does not help heat your living space even though it does great for the basement . Peace and good luck clammy

JUGHNE

I am thinking that the water is pushed out the return up each equalizer and possibly into the old second header....possible water hammer there??

Installer could have changed the slope of the counter flow main, making it slope the wrong way.....but would that water have returned to the boiler?

Waiting for more pictures.

ethicalpaul

Here is what a new boiler does before it is skimmed:

 https://youtu.be/jvt8qxBaRJU

EBEBRATT-Ed

Probably needs skimming

The piping may be too small.

What is the EDR capacity of the boiler

More IMPORTANT

With 2 equalizers the difference in pressure between the two steam headers could have something to do with the unstable water line

clammy

How high is your header from your water line .as stated before counter flow system like dry steam and low pressure due to the system drip being usually not much a dimension . Get a low pressure gauge and add it to the pressuretroll assembly and be sure that the pressure trol is set a slow as possible if your still having issues I would suggest a good boiler fluxing and skimming and possibly a wanding I would image there was a lot of oils in all those piping nipples which I’d going to really cause some surging . The low pressure gauge will tell the tale if the pressure is to high your gonna have issues . As other have said is the boiler sized correctly .? What’s the edr and is the boiler piping at least the mim required by the manafacture ? Counter flow can be difficult and will not function correctly unless provided w dry steam, a over sized drop header and a vaporstat would have been the correct path for proper operation . The fact your water line rises quickly I again would suggest to up date radiator vents if it has not been done . Peace and good luck clammy

greg556

Hi everyone, three days later. It's miraculous. After the first two responses, I skimmed the boiler water. I don't have any other word for it; miraculous. Skimming solved EVERY problem we were seeing. The water in the gauge now bounces up and down in the middle, never more than an inch either direction. The hammering stopped completely, and the hammering was SEVERE before this. And both of the radiators that were not working started working fully again. The radiators are now heating according to the settings on the vents (6 first, 1 last) (all of the radiator vents are brand new Hoffman adjustables).

About 12 hours later, the behavior started to return. I have skimmed it twice more and that seems to have done the trick. As far as I can tell, no contractor in Minneapolis is aware that skimming is required after installation. I think I'm going to be single-handedly, with your help, improving the steam boiler knowledge for this entire area for decades to come.

Thank you all so much; it's just amazing that you went directly to the problem after one question from me.

Here are a few more comments in answer to some of the questions posed here. Yes, the system is counter-flow--the condensate comes back in the same pipe as the steam leaves. I think that is what looked odd to a couple people--that pipe to the bottom of the Hartford loop is not another equalizer, it's the condensate return. The boiler does have a skimmer port; I didn't include it in the pics because it's not really relevant to the near-boiler piping.

Finally, I have some observations you might be interested in. What is happening is the oil on the boiler water is creating some kind of suction action that is sucking the water from the bottom of the boiler out of the boiler and into the return pipe; that's why the level is dropping so quickly. (Very interesting, it's also why the boiler never triggered the LWCO. No matter how much water is in the boiler, it drops down to the same spot; it's because the level is a function of the suction strength, not the amount of water.)

Finally, there is an interesting piece of evidence that this is what is happening, for your future reference. When the boiler is functioning normally, the output pipes heat first, and then eventually the return pipes heat from the top down as the condensate begins to return. The equalizer hardly heats at all until the whole system is heated up. When this suction action is happening, the return pipe heats up BACKWARD! (And the equalizer pipe gets very hot very quickly as well, from the bottom up.) It is clear that the water is traveling from the bottom of the boiler through the Hartford loop and UP the return pipe, in our case to a point about four feet from the ground. It's very easy to tell whether this problem is happening--the return pipe heats backward. If you see low water, check whether the return pipe is heating backward before you install an automatic feed!

Thank you all again so much. I am really hoping that when I explain to the contractor what was wrong, he listens to me and starts including skimming in future installations. If he has any integrity, he should contact the owners of every boiler he's installed in the last ten years and ask to come out and skim them. Who knows what kinds of problems have been misdiagnosed because this simple procedure has not been followed.

mattmia2

greg556 said:

Finally, I have some observations you might be interested in. What is happening is the oil on the boiler water is creating some kind of suction action that is sucking the water from the bottom of the boiler out of the boiler and into the return pipe; that's why the level is dropping so quickly. (Very interesting, it's also why the boiler never triggered the LWCO. No matter how much water is in the boiler, it drops down to the same spot; it's because the level is a function of the suction strength, not the amount of water.)

Finally, there is an interesting piece of evidence that this is what is happening, for your future reference. When the boiler is functioning normally, the output pipes heat first, and then eventually the return pipes heat from the top down as the condensate begins to return. The equalizer hardly heats at all until the whole system is heated up. When this suction action is happening, the return pipe heats up BACKWARD! (And the equalizer pipe gets very hot very quickly as well, from the bottom up.) It is clear that the water is traveling from the bottom of the boiler through the Hartford loop and UP the return pipe, in our case to a point about four feet from the ground. It's very easy to tell whether this problem is happening--the return pipe heats backward. If you see low water, check whether the return pipe is heating backward before you install an automatic feed!

It isn't that it is getting sucked or pushed up the return but that a large quantity of hot water from the boiler is being thrown up in to the main and running back through the return so that hot water is heating the return instead of the steam heating the whole surface of the main.

When there is oil on the surface the steam has trouble escaping the surface of the water so it escapes violently in bursts taking a lot of water with it instead of emerging relatively gently and continuously from the surface.

when it is steaming properly the return gets little water in it until the pipes heat and begin condensing steam and that condensate runs back in to the return.

EBEBRATT-Ed

@greg556

Good detective work. Oil and dirt on the surface of the boiler water will drive a boiler nuts as you have found

The return pipes heating from the top down is normal

Sounds like the boiler is/was shoving the water up the return if it was getting hot

I would strongly suggest you check the operation of the low water cutoff and check/clean the probe. You need to know that that safety control works

BobC

Skimming often has to be done more than once to get all the oils out. I always took a good 2 hours to get 5 gallons out with a very thin line of water coming out the skim port.

Bob