Steam Boiler Replacement Water

kub1080

Hello - I have a Thermoflo GSA 125,000 BTU steam boiler installed in 2014 when we moved in. I have a question on how often the boiler should need replacement water. I filled the gauge glass to about 1/2 way up 2 days ago and noticed today it dropped to almost a 1/4 of the gauge glass.  We have an automatic feeder and the counter only increases about 2 gallons an entire heating season so I was surprised when I saw the water level drop in 2 days.  I don’t usually check the boiler water level daily so I’m not sure if this is normal.  I checked all the radiator valves and air vents and didn’t notice any steam leaking out anywhere.  It has been very cold here recently and the boiler has been running a lot.  Could be that just be normal water loss?  

Jamie Hall

It could be, but it seems unlikely. But before you become concerned, make sure that you are checking the water level with the system in more or less the same condition -- that is, when the boiler has been off for at least 15 minutes. Somewhat slow returns can make the water level appear low when the boiler has just been running.

kub1080

Jamie, thank you very much for the advice. I refilled the boiler gauge glass to halfway and made a mark where I filled it to.  I’ll try checking it in the next few days after the heat has been off for at least 15 minutes.  I’m not sure it was off for 15 minutes when I looked at it today with the cold weather we’re having in the northeast. 

kub1080

Jamie Hall said:

It could be, but it seems unlikely. But before you become concerned, make sure that you are checking the water level with the system in more or less the same condition -- that is, when the boiler has been off for at least 15 minutes. Somewhat slow returns can make the water level appear low when the boiler has just been running.

Hi Jamie,

I took your advice and checked the water level today after the boiler was off for a bit. I filled the boiler yesterday halfway up the sight glass to the black line and then checked it today when I got home from work. I turned the boiler off and waited 30 minutes and there was some water loss. The first photo is from yesterday after I filled it and the second is today. Do you think I should be concerned about the water loss or could this just be normal?

Jamie Hall

Honestly that is more water loss than I would expect from a day of running -- even in cold weather. Time to go looking for anywhere and everywhere there might be a leak. Keep in mind while you do this that there is no such thing as a trivial leak: even one drip every 10 seconds will add up to a gallon in a day!

kub1080

Jamie Hall said:

Honestly that is more water loss than I would expect from a day of running -- even in cold weather. Time to go looking for anywhere and everywhere there might be a leak. Keep in mind while you do this that there is no such thing as a trivial leak: even one drip every 10 seconds will add up to a gallon in a day!

Thanks for the advice!  I checked all the radiator  air vents and valves and I didn’t see any leaks.  I have my plumber coming on Friday morning so hopefully he’ll have some ideas as I’m not really sure where else to check. One thing I did notice was that there was a lot white smoke coming from my chimney this morning. I assumed it was just condensation because of the cold weather. Could this possible be the steam from a leak in the boiler? We had the boiler installed in 2014 so it isn’t that old. 

https://youtube.com/shorts/_XyiJk8lzCg?feature=share

Jamie Hall

That doesn't look too bad. But it would be worth checking. I should last longer than that -- but we all have seen boilers which failed sooner, often from installation issues.

ethicalpaul

Just checking, but you are looking for leaks during long calls for heat, as opposed to when the boiler isn't firing, correct?

kub1080

ethicalpaul said:

Just checking, but you are looking for leaks during long calls for heat, as opposed to when the boiler isn't firing, correct?

Hello- I have been looking for the leak while the boiler is running. I bumped the temperature a few degrees and waited for the steam to reach the  radiators and then checked the air vents and the radiator valves. I don’t have any buried pipes in the ground and haven’t noticed any signs of moisture on any of the walls where pipes may be hidden.  I’ll try looking again after letting the boiler run a little longer like you mentioned. 

Any suggestions on where else to look to find the possible leak?

EBEBRATT-Ed

@kub1080

You can use a small mirror to check for steam leaks. Steam can leakand you can't see it. Hold the mirror near the air vents and around the radiator supply valves . If there is a leak the water vapor will usually condense on the mirror

Jamie Hall

sophia123 said:

Jamie Hall said:

Honestly that is more water loss than I would expect from a day of running -- even in cold weather. Time to go looking for anywhere and everywhere there might be a leak. Keep in mind while you do this that there is no such thing as a trivial leak: even one drip every 10 seconds will add up to a gallon in a day!

Really helpful advise.

About the best I can do. Chasing small leaks, particularly in older systems, is one of the most frustrating tasks I can think of!

ChrisJ

Jamie Hall said:

sophia123 said:

Jamie Hall said:

Honestly that is more water loss than I would expect from a day of running -- even in cold weather. Time to go looking for anywhere and everywhere there might be a leak. Keep in mind while you do this that there is no such thing as a trivial leak: even one drip every 10 seconds will add up to a gallon in a day!

Really helpful advise.

About the best I can do. Chasing small leaks, particularly in older systems, is one of the most frustrating tasks I can think of!

I suppose you could remove all of the air vents and plug the holes and then pressure test the system with air at 10 PSI or so and go around listening and using soapy water.

That's probably the fastest and most sure way if you have the time and know how.

On my system I had a union leaking but it was only noticeable when steam first got to it as it would make a slight sizzling noise, but then it'd stop and anything wet dried up immediately.

Jamie Hall

One of the most annoying leaks I have found was a very minor drip way out in the wilderness on the threaded connection between a riser and a horizontal run on a dry return. About a drip every 20 seconds. Accounted for a solid gallon per day...

kub1080

Jamie Hall said:

One of the most annoying leaks I have found was a very minor drip way out in the wilderness on the threaded connection between a riser and a horizontal run on a dry return. About a drip every 20 seconds. Accounted for a solid gallon per day...

I’m really hoping I might be able to find the leak with the mirror trick that was mentioned by EBEBRATT-Ed. We have a finished basement and outside of the boiler room all the steam pipes are hidden. The steam pipes you can see are encapsulated since they have asbestos insulation.  I checked the boiler again this morning after it was off for 20 minutes and the water level looked about the same as last night. I marked it with some tape to see if it drops some more today.  I am thinking if there was a leak in a hidden pipe it would show some moisture on the wall or ceiling since a small leak could amount to a gallon a day like you said.  

kub1080

I think I have found the leak. It’s a small drip.  My plumber is coming tomorrow morning so hopefully this is an easy fix. I better check all the valves again since I missed this the first time I checked. 

https://youtu.be/RFsihfcVnc4

Do you think this small drop could account for all the water loss I’m seeing? 

Thanks for the help,
Dan

cross_skier

Yes I do

Jamie Hall

Let's run the numbers... 1 drop, say 0.5 ml, every 3 seconds or so. 10 ml per minute. 0.6 litres per hour. 14 litres per day... almost 4 gallons... yeah. Although I may have overestimated drop size and underestimated frequency... but even so, and even if it only does it when the boiler is running...

Yeah.

See what I mean by even a small drip can account for a lot of water?

kub1080

Jamie Hall said:

Let's run the numbers... 1 drop, say 0.5 ml, every 3 seconds or so. 10 ml per minute. 0.6 litres per hour. 14 litres per day... almost 4 gallons... yeah. Although I may have overestimated drop size and underestimated frequency... but even so, and even if it only does it when the boiler is running... Yeah. See what I mean by even a small drip can account for a lot of water?

When you put it that way it makes sense.  Thanks for your help with this. 

ethicalpaul

nice job on the find, so satisfying!!

kub1080

The leak is fixed!  Turned out the nut was loose. It is a very tight space where the connection is made, but my plumber was able to tighten the nut a half turn and the leak stopped. 

One other question.  This morning I heard what I thought was the usual sound of air coming through a few of the air vents.  However, the heat was on a long run after being lowered at night. They weren’t spitting water but when I held a mirror it instantly fogged right up. Is that a definite sign it is leaking steam?  I had tried this test earlier in the week and saw nothing on the mirror from any of my radiators, but that was in the evening after heat was on maybe 15 minutes. 

I don’t see any steam coming out of the vent but the entire radiator was warm from the boiler running for a while. Just wondering if I should replace the 3 air vents?  I’ve been using the Varivalve Ventrite #1 which I liked due to their adjustable setting. 

kub1080

Now that I had the leak repaired on Friday morning 1/14, I lost maybe an 8th of an inch or less of water as of this afternoon 1/8. I am assuming that this is what would be within the limits of normal water loss for four days. Would you agree?

Pissed123

I had the same boiler installed in May of 2006 and it worked fine for years, but in January 2022 I notice the automatic water feeder kept going off frequently. When I checked steam was coming out of the top. I immediately called my utility company and they shut it down, because of the risk of carbon dioxide poisoning. Long story short the top of boiler (heat exchanger) was totally rusted out, so I had to replace the boiler. I did contact the company Weil-Maclain and they said their warranty is only for 10 years (the woman was very rude). I would think that a boiler that's only used a few months a year would last longer. I know people with boilers 20 + years old. This boiler is definitely a safety hazard!!

Pissed123

OOps! I meant carbon monoxide in the previous post.

KC_Jones

Pissed123 said:

I had the same boiler installed in May of 2006 and it worked fine for years, but in January 2022 I notice the automatic water feeder kept going off frequently. When I checked steam was coming out of the top. I immediately called my utility company and they shut it down, because of the risk of carbon dioxide poisoning. Long story short the top of boiler (heat exchanger) was totally rusted out, so I had to replace the boiler. I did contact the company Weil-Maclain and they said their warranty is only for 10 years (the woman was very rude). I would think that a boiler that's only used a few months a year would last longer. I know people with boilers 20 + years old. This boiler is definitely a safety hazard!!

Couple things here. The boiler rotting out on the steam side has no impact on the combustion gases leaking into your house, so the person that told you that was either not properly educated or flat out lied.

Second, the boiler having a short life most likely is due to improper installation, or improper maintenance. That boiler is a rebranded Weil Mclain, and I can tell you first hand those boilers will last if properly installed an maintained. I had one go 32 years, and I put another one in and I plan on it lasting longer with water treatment.

People want to go after manufacturers in these situations, and most of the time that isn't justified. Based on what is posted on this website regularly, most of the time its the contractors fault.

The boiler isn't a safety hazard, the people you have been listening to are.

Jamie Hall

I'll ad to @KC_Jones comment there -- water quality isn't what causes problems at the top of a boiler, although it can cause corrosion below the water line -- if, and only if, too much water is being added because of leaks elsewhere. Such as might be caused by sloppy installation of the boiler.