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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 Easy to use and works! Had a small leak somewhere inaccessable, so drained the system a bit, poured into top of bathroom towel rail (highest point), refilled and bingo. No leak. 23 Jan 2016
Rated 5 out of 5 by Finally. Job done. After a very long time suffering the inconvenience of the boiler not coming on in the morning because of the loss of pressure overnight we are finally waking up to a warm house. Adding the sealant could not have been easier. I used a towel radiator upstairs as this is the highest point and filling through the top vent is straightforward. Vent any remaining pressure from the system, drain off a litre(ish), remove the vent plug from the radiator, empty contents into system, refit plug, pressurise system and let the sealant do the work. Hey presto! No loss of pressure to date. For this price and the short time to do the job it can only be 5 star and it only needs 2 words. It works. 21 Jan 2016
Rated 5 out of 5 by Simple and affective sealer Since moving in a year ago have had to replace most radiators as they had pin holed over several months during this time and kept loosing pressure and having to top up system. I had assumed this was due to radiator leaks but problem continued. As the pipe run is plastic pipe set in floor with copper tails to radiators it is impossible to locate actual leaks. I have assumed the compression joints in floor have been disturbed when fitting new radiators which are metric size to replace imperial ones. Having purchased product I drained required amount of water from system using air vent plug on bedroom radiator and filled system through bathroom ladder radiator, which has vertical bleed vent in top. This made it a simple way to pour fluid into system with jug. I found it required the bathroom radiator to be fully opened to distribute around total system. Result a system which is not leaking and has not required topping up. (Only after 1 week hence only 3 * for reliability.) So far so good! 31 Dec 2015
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
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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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9 Sep 2015
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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