Hercules 1 qt. Boiler Liquid-30115 - The Home Depot


Model # 30115

Internet # 100147992

Store SKU # 654921

1 qt. Boiler Liquid

Hercules 1 qt. Boiler Liquid

This item has been discontinued.
The Home Depot no longer carries this specific product.

$8.54 / each


Model # 30115

Internet # 100147992

Store SKU # 654921

HERCULES 1 qt. Boiler Liquid is used to seal and repair cracks and leaks that appear in steam and hot water systems. The odor-free formula creates a tough seal that expands and contracts with heat. NSF registered and USDA authorized.

  • Seals and repairs cracks and leaks in steam and hot water systems
  • Compatible with propylene glycol-based antifreezes, chemical additives and boiler treatment compounds
  • Will not clog hot water coils, controls, valves or vents
  • Resists high pressure and is not affected by boiler cleaners

Info & Guides

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Assembled Depth (in.)  3 in  Assembled Height (in.)  9 in 
Assembled Width (in.)  3 in  Product Depth (in.) 
Product Height (in.)  9.0  Product Width (in.) 
Accessory type  Heating  Heating Product Type  Accessory 
Heating Technology Type  Radiant  Product Weight (lb.)  2.39 lb 
Returnable  90-Day 
Warranty / Certifications
Manufacturer Warranty  1 year 


Rated 4.6 out of 5 by 7 reviewers.
Rated 5.0 out of 5.0 by Must have for outdoor wood burner users I confess I was lured into purchase of the cheap stainless steel ( not stainless at all) Canadian manufactured outdoor wood burner boiler. Even with keeping the required chemicals in the water at all time within three years it leaked like a sieve. Rusted in every seam. The real problem is this so called stainless steel is almost impossible to weld as compared to mild steel. This boiler was guaranteed 10 years except if it leaks then you own it. This boiler liquid has saved my boiler. Period. Whether it is the tubes inside the firebox leaking or the seam at the lower rear, this stuff works with absolutely no issues for the air to air heat exchanger or the water to water heat exchanger, the circulating pump, or the piping/valves. Better get some and keep it handy. December 17, 2014
Rated 5.0 out of 5.0 by Performs as described. Used in an outdoor wood fired boiler that had some pin hole or smaller leaks. Followed product instructions and leaks stopped almost immediatly. Has been about a month since added and no leaks. January 15, 2014
Rated 4.0 out of 5.0 by Hercules 1 Qt. Boiler Liquid - Leak Gone Product easy to introduce into system. Continuous drip in boiler has been eliminated. No system performance problems observed due to introduction of product into heating system. Ordered two quarts and only needed to use one quart. Produect used On - Residential Hydronic Radiant Heat Boiler System 175,000 Input/135,000 Output, 21 PSI Static Pressure, 30 PSI Relief Pressure, Operating Temp. Approx. 140 degrees F. Boiler Age: Installed 1964. November 5, 2013
Rated 5.0 out of 5.0 by Works as advertised! A week before heading out on vacation I discovered a leak in a pipe joint on my boiler. Not having enough time to get a plumber in to repair the problem I tried some plumbers putty and other temporary sealants to resolve the issue. Each of these seemed to slow the leak down, but did not completely stop the problem. With just a couple of days left I decided to give this product a try. I followed the instructions unscrewing the pressure releif valve and pouring the product into the boiler. After reinstalling the releif valve I fired up the boiler. I was stunned to see the leak completely stop within minutes. I held my breath as the boiler pressure rose as this is when the other products failed. No sign of the leak reappeared. I checked the boiler over the next two days and was happy to see that the boiler remained dry and the water level in the boiler remained intact. This is a wonderful product! February 3, 2013
Rated 4.0 out of 5.0 by sofarsogood easy to use took a long time but seems to be working January 27, 2015
Rated 5.0 out of 5.0 by This product works wonders. I had a leak in my boiler and it keep putting out the piolit light, had to do something so I figured I will try this stuff; I am really surprised with the results.It didn't only stop the leak but when it dried it showed the size of of it. I would use this product again if needed to. March 25, 2013
Rated 4.0 out of 5.0 by It plugged the leak I ordered a bottle from Home Depot, but when reading the instructions found out I needed 5 more. I ordered the rest from Lowes, since Home Depot had a huge shipping charge. Maybe it was a mistake on Home Depot's system. Followed the instructions, but isolated each of the 3 zones of my radiant floor to be able to reach 180 F out, 135 F coming back. By the way, I electrically bypassed the burner high limit to keep it going. Recommend getting someone who knows what he/she is doing if your controls don't allow you to safely set 180 F in your boiler. The hotter the better. Then I increased the pressure from 5 to 20 PSI and saw the pressure go down to 5 again. Subsequently I increased it to 25 PSI and witnessed, with amazement, that the hole apparently was closed. I kept it there for two hours at full fire. I told my wife the house was going to get hot. I am glad I warned her, otherwise I would not be writing this now. Report: No pressure loss for the last 24 hours. If it last for the next few winters it would be a huge success. Will see. Good luck to you. April 22, 2014
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