Steam coming out from behind the boiler...

KconQueso

Hey all,

I have a bit of an issue with my boiler and have seen that the people here seem to know a lot, so I was hoping I can get some advice.

I have a Weil-McLain EGH-95 low pressure boiler in my building that was installed in 2011. About a month or two ago I noticed a bit of steam emanating from behind the boiler. Not a lot (think of a pot simmering), but enough that you can see it coming out when you enter the boiler room.

In early December, I had gone to the boiler to inspect it and added a little water to it as the gauge showed that it was low. I didn't fill it all the way obviously. I then noticed some water coming out of it and immediately turned it off to inspect it. The water flow stopped but it wouldn't turn back on so I called a plumber who got it working again and inspected for a water leak, which there was thankfully none. Using an endoscopic camera though we did look underneath and noticed the sections were a little wet. While there has been no water leak since then, later that evening I did notice the steam for the first time. I texted him and he said that it may self-seal (which it hasn't).

The amount of steam hasn't changed since I noticed it and it only seems to happen when the boiler is on for a long period of time or on very cold days. From the research I've done so far, my understanding is that there may be a small pinhole leak or crack on one of the sections above the water line or possibly one of the gaskets between the sections has wasted away.

I lowered the temperature by 2 degrees to 71F, the pressure in the boiler has remained low (>5psi), and there are no major signs of corrosion on the system. I think the problem is small enough that we can get through the winter, however, the gas bill has gone up by a lot in the last 2 months and I want to try to tackle this issue if possible.

If I'm not mistaken, there are boiler sealants (like Hercules) that can address water leak issues, but my understanding is that those probably won't work if it's steam and the leak is above the water line. I was thinking of taking off the boiler's top cover and insulation layer and seeing if I can visually see any cracks or pinholes. Maybe also turn off the boiler and fill it all the way to see if it leaks water from near the top? Are there any sprays, epoxys, or sealants you can recommend I can use for upper sections or gaskets?

Any and all advice is appreciated. Thank you in advance.

EdTheHeaterMan

Sounds like you have a leaker just above the operating water line. the way you test for a leak above the water line is to put more water in the boiler until it gets to the top of the equalizer piping. Sounds like you already did that by accident back in December.

At the next emergency budget meeting, you need to bring up the subject under new business: purchase of a new boiler.

mattmia2

You should find someone to install the new one that can figure out what system problems killed the old one too, they should last more than 15 years unless there are leaks in the system causing a lot of fresh water to be added or the piping is incorrect such that it is pulling the sections of the boiler apart.

EdTheHeaterMan

Actually as a temporary fix, you can try to use Boiler Solder to fix a leak above the water line. You get the boiler solder water mixture inside the boiler with the water line below the leak. Then you heat the boiler to make steam. Then you slowly add water to the boiler and continue to make steam. When the water level gets to the leak the boiler solder will fill the void and you will have a few months until you need to replace the boiler.

KconQueso

https://forum.heatinghelp.com/discussion/comment/1840493#Comment_1840493

I have a feeling there may possibly be an issue with the automatic water feeder. The water line in the gauge usually is low on the glass tube so I'm thinking it's feeding it more than it should… Of course, it might be something else.

mattmia2

It only feeds if it is leaking out somewhere like through bad vents or leaking valves or piping or now though the hole in the boiler.

A little bit evaporates because it isn't a completely closed system but it should only lose a couple gallons a month or less.

Jamie Hall

I hope that the pressure comment was a typo — ">5 psi". I hope you meant "< 0.5" psi. But I'm not counting on it…

Check the cutout pressure of the system. If this is a residential or relatively small commercial system it should be less than 2 psig…

KconQueso

https://forum.heatinghelp.com/discussion/comment/1840495#Comment_1840495

Just so I got this right:

I add it to the boiler with some water (below the leak). I close it back up and turn it on. Then I slowly add water until it reaches the hole/crack. Then, presumably, the water will leak out of there and as it leaks, the solder will begin filling in the hole and seal it. Have I understood the process correctly?

My only question then would be: Where would it go in through? I'm assuming one of the pressure relief pipes? The plumber who came through said the Hercules would go through the 15psi pipe.

Also, is there anything I can do if it's a gasket? Like maybe something like this?:

https://www.amazon.com/Red-Devil-0897-Temperature-Silicone/dp/B008O0Y2Y8?th=1

KconQueso

https://forum.heatinghelp.com/discussion/comment/1840511#Comment_1840511

The plumber told me the boiler has 3 pressure points where it would shut down if pressure got too high—5, 10, and 15 psi. I just said under 5 because it's never gone beyond that. It's usually between 1-2 (though I have seen go a bit above that once in a blue moon).

EdTheHeaterMan

Correct description fo the Herculies boiler solder process.

Pour the power you mix with water into any opening that you can access. The skim tapping may have a larger opening but the relief valve opening is fine. Follow the instructions that comes with the product.

Trying to seal a leak from outside will be a exercise in futility.

Jamie Hall

The 0 and 15 may be sort of OK… as they are emergency backups.

The 5 is two and half to three times as high as is needed. Even the Empire State Building operates on 2 psi.

Send us a picture of the pressure control devices, and we can advise on how to fix the problem.

Won't help the leak now, though you will lose less water and less fuel (and money)…

yellowdog

Please don't allow that plumber back into your building.

Steamhead

@KconQueso , where are you located? We might know someone who can be more helpful……………