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Sentinel Internal Leak Sealer 1Ltr

Product Code: 99730

Internal Leak Sealer for small inaccessible leaks and weeping joints in all types of indirect heating systems including those containing aluminium components. Compatible with elastomers.

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Rated 5 out of 5 by Extremely impressed I had a minor leak on my 9yr old Baxi combi boiler, that was a steady and continued rate of drip. My gas service engineer advised what would be involved in the repair, but agreed that this stuff would be worth a try to save money. I fed this into the system via my bathroom towel radiator, using a funnel, then set the heating to run. Within 15 minutes the leak was sealed. It's fair to say that I'm more than happy with the result. It certainly buys me some time before I may have to repair or replace the boiler. 15 Nov 2015
Rated 5 out of 5 by It rally works Lost pressure in system ,could not find leak under restricted accsess of house so decided to buy this product . Almost bought a cheaper alternative but rally wanted this problem sorted .after draining system and installing this product 24 hours later problem solved ! 21 Oct 2015
Rated 4 out of 5 by Where is the leak? I have a small leak in a pipe joint of the central heating system at my holiday home. The house has tiled and concrete floors so each spring after the system has been drained down for winter I have to replenish the system with the leak sealer and everything is OK for another year. A lot cheaper than excavating the floor and re-tiling and works every time. 16 Oct 2015
Rated 5 out of 5 by System stop leak Easy to use done the job saved taking up laminate flooring 16 Sep 2015
  • 2015-11-25 T09:50:40.372-06:00
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1 Question  1 Answer

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8 Sep 2015
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Hi there, Sentinel Leak Sealer can be added to the system in a number of ways. For open vented systems, dose via the expansion tank during the final fill. For empty sealed systems, add to any convenient point before filling. For full sealed systems, use a Sentinel Dosing vessel to inject via the filling loop or other access point. Sentinel Leak Sealer is also available in Rapid-Dose format
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Customer Service
9 Sep 2015
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  • 2015-11-25 T09:44:07.501-06:00
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Download more info (pdf)

Brand Sentinel
Colour White
Manufacturer Guarantee 1 years
Manufacturer Guarantee 1 years
Pack Size 1
Product Type Internal Leak Sealer
Sealant Adhesive Volume 1 Ltr
Total Product Weight 1073 kg