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Sentinel Leak sealer, 1L
- Seals inaccessible leaks and weeping joints internally.
Features and benefits
- It can make better use of resources to repair rather than replace items
Health and safety
Please note that this item has additional safety or regulatory datasheets available. The product may have possible health and safety hazards covered in these documents. Refer to the container for full information and always follow the instructions.
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Long lasting fix for leaks
HarmanG - 1 year ago
I refurbished an old cast iron radiator. Did a leak check before hand and was happy not to see any watering leaking from it. So installed it in my kitchen. However, next day there was water on the kitchen floor from two small leaks between the sections of the rad. Had a look online how to tackle the problem and was lead to Sentinel Leak sealer. I poured it into my expansion tank and it stop the leak within minutes. That was 6 months ago and still no leak so I really recommend this product
Bodr - 3 years ago
My old Worcester 24cdi was dripping from the expansion vessel , losing pressure every day . I added sentinel leek stopper to a radiator and over the next few days the leak was almost non existent . I'd imagine that over the next few days it will stop altogether . Highly recommended
Stopped pulling in air.
Thedeester1 - 6 years ago
After fitting a new bathroom the boiler started to bang and I was having to bleed air from the system every few days! I looked everywhere for a leak that might be pulling air where I had made alterations but couldn't find any obvious leaks. Rather than lift every floor to find a leak that didn't seem to be dripping water I tried this product. Its been over a week now with no boiler banging and when the bleeds are opened there isn't any air! I recommend this product for any one that has a leak that doesn't appear to exist!