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1 qt. Boiler Liquid
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$8.70 each
In Stock
In Stock
Get 174 Tue, Jul 29
Free Shipping On orders over $99
Easy Returns No restocking fee for 90 days

Product Highlights

Product Highlight: Volume
32 oz.

Description

Features:
  • Seals and repairs cracks and leaks in steam and hot water systems.
  • This liquid formula will not clog hot water coils, controls, valves, or vents.
  • Forms a tough seal that expands and contracts with heat.
  • Resists high pressure and is not affected by boiler cleaners.
  • No odors - no priming - no foaming.
  • Does not contain petroleum distillates.
  • Compatible with Hercules cryo-tek or other types of propylene glycol-based anti-freeze products, chemical additives and boiler treatment compounds.
  • NSF registered/USDA authorized.

Specs

Product Type:

Boiler Liquid

Application:

Leak Prevention

Volume:

32 oz.

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Product Reviews

4.7 out of 27 reviews
90% would recommend this product
4.7
out of 27 Reviews
90% would recommend this product
WRITE A REVIEW
5 star
85%
4 star
4%
3 star
7%
2 star
4%
1 star
0%
WRITE A REVIEW

Most Liked Positive Review

This stuff really works

I have owned an outdoor wood burning furnace for more than five years. I love the engineering. However, I was talked into buying "an upgrade" stainless steel "never rust" boiler. Don't do it. What I received was a 409 SS ferritic steel that is the lowest grade of SS and corrodes with a passion. However, it is very difficult for the average welder to weld it so it won't leak. Combine the corrosion issue (worse than mild steel) and lack of being able to weld it to patch the leaks and you have an expensive paperweight. Thanksfully, I have used Hercules Boiler Liquid for several years and it absolutely works without plugging up the rest of the system or interfering with the heat exchangers. The price is right, the shipping is fast, and it works, you can't beat it.
VS

Most Liked Negative Review

When adding to outdoor wood boiler.

Do I need to drain the water to the point of the leaks then add the sealant and water keeping the temp up? Or can I just add to the system and keep the temp up and watch the leaks.
Showing 1-10 of 27 reviews

Boiler liquid

1 quart stopped a small leak on my taylor 450 for 10 days. Then started dripping again and I added another quart and it stopped leaking. That was 11 days ago and still not leaking.
688i
Va
5 months ago
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good

stopped the leak enough to get them through the heating season
me
michigan
5 months ago
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I wouls buy this again as needed

Used in a hot water solar collector with some leaking solder connections. mStops leaks for a while
willie
southeastern PA
1 years ago
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Great service and pricing

It works as described.
C
The Dalles Oregon
1 years ago
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boiler liquid

worked as advertised
Jim
western New York
3 years ago
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Amazing Stuff

I had leaks in my wood boiler tubes under pressure. One application and it was sealed.
Highlander
West Virginia
3 years ago
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Yes

Several years ago we had a crack in the boiler and used a product that worked but same leak showed up again used Hercules boiler stop leak and used as per directions and worked great. I was happy with Supply House, shipped and keep me up to date as when I would receive the product will order from them again if need anything else.
Mark
Northwest Kansas
3 years ago
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for sure

cast iron had exploded , crack and pinholes.... nobody believed this liquid could work but it completely sealed the cracks... i did follow directions carefully , keeping everything hot etc...
loops
holler
3 years ago
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YES I WOULD BUY AGAIN

IT WORKED
NONE
WASHINGTON DC
4 years ago
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No

yes did not work
Ron from Michigan
Michigan
4 years ago
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Product Q&A

4 Questions
4 Questions
ASK A QUESTION

Q: I have Pex in my heating system. I have a leak in a metal threaded coupling. Is 'Hercules Boiler Liquid Leak stop' compatible with the pex (oxygen barrier pex)?

Asked by Steve 8 years ago

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Verified Author and ReplyVerified Reply- SupplyHouse Staff

Yes, it is.

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Q: Is this product safe to use to try to stop a leak in a residence hot water heater (40 gallon unit)?? Most of the descriptions and instructions mention only boilers and hot water systems. I just want to make sure that I can safely use this product to heat water that will be used throughout the household (showers, dishwashing, etc.).

Asked by Nick 9 years ago

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Verified Author and ReplyVerified Reply- SupplyHouse Staff

No, this is only suitable for heating systems. If a water heater is leaking you have to replace the unit.

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Q: How many quarts will i need for a 150 gallon system?

Asked by chris 9 years ago

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Verified Author and ReplyVerified Reply- SupplyHouse Staff

Hercules lists usage instructions based on boiler size, not system capacity. The chart can be found in the product literature here on our site : http://s3.supplyhouse.com/manuals/1277918330238/34049_PROD_FILE.pdf

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Q: It seems that all of the reviews for this product are related to leaks in the actual boiler itself. At this point, I can only assume there is a leak in my system, but have no idea where. I don't see any leaks or moisture around the boiler itself so I presume the leak is somewhere in the piping of my system. Can this product seal leaks throughout the entire system loop of copper piping? I have a hot water baseboard radiator system along with an annoying and problem-prone towel warmer rack. I look forward to hearing from you. Thanks, Peter Minneapolis

Asked by Golden Valley Pete 12 years ago

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Hi - I had a small internal leak in my boiler that this product fixed. The leak was not visible and there was no water to be found. I am guessing that it was between the gaskets and the boiler plates. The small leak was evaporating before a puddle was found. So if your leak is small this product will likely fix it, but large leaks need to be fixed with other means. Good luck-

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On orders over $99
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