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Used throughout domestic heating systems for sealing smal,l inaccessible leaks. Compatible with all systems metals. Easily applied via radiator with the patented applicator.

Used throughout domestic heating systems for sealing smal,l inaccessible leaks. Compatible with all systems metals. Easily applied via radiator with the patented applicator.
Average Customer Rating:
4.889 out of 5
4.9
 out of 
5
Open Ratings Snapshot
Rating Breakdown 9 reviews
5 stars
8
4 stars
1
3 stars
0
2 stars
0
1 star
0
9 of 9(100%)reviewers would recommend this product.
Customer Reviews for Fernox Heating Leak Sealer Superconcentrate 290ml
Review 1 for Fernox Heating Leak Sealer Superconcentrate 290ml
Overall Rating: 
5 out of 5
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5 out of 5
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5 out of 5
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Would you recommend this product? Yes
Overall Rating: 
5 out of 5
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Best of the bunch
4 Feb 2014
By GKni
, Shepperton
" Not cheap compared to some of the other similar products, but well worth it as this one really works!
Easy to use, the supplied connectors ensure easy mess-free injection, whether into a radiator or the boiler's charging loop, you just need to provide your own skeleton gun.
Many manufacturers warn against using these injectable sealants as they can clog the elements in the boiler, it's worth mentioning than this is the ONLY such product that Worcester Bosch specifically endorse. "
3 of 3 people found this review helpful.
Review 2 for Fernox Heating Leak Sealer Superconcentrate 290ml
Overall Rating: 
5 out of 5
5 out of 5
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5 out of 5
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5 out of 5
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5 out of 5
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5 out of 5
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Would you recommend this product? Yes
Overall Rating: 
5 out of 5
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5 out of 5
AMAZING product
24 Dec 2013
By tallmark
, Portsmouth
" This is the stuff plumbers do not want you to know about!
I had a leak in the central heating system under the floor. My boiler pressure was going from 1.5 bar to nothing within 12 hours so it was a significant leak and to solve the leak I was faced with taking up the newly laid floor in the living room and potentially needing to get the kitchen/ bathroom pines re-laid as they are in a concrete floor.
Faced with the above I thought I would give this product a go but didn't hold out much hope as all other leaks I read reviews on seemed minor in comparison to mine.
I tried this product and it worked straight away - no more topping up the boiler, no more leak! I fixed the leak 3 months ago and its been totally fine since. I don't know how this product works but its amazing.
I would totally recommend this product as a much cheaper and much easier alternative to a plumber!
One thing I would say as while this product can be put into the heating system on your own, its easier if you have someone to help you as 3 hand are sometimes useful! "
6 of 6 people found this review helpful.
Review 3 for Fernox Heating Leak Sealer Superconcentrate 290ml
Overall Rating: 
5 out of 5
5 out of 5
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5 out of 5
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Features: 
5 out of 5
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5 out of 5
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5 out of 5
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Would you recommend this product? Yes
Overall Rating: 
5 out of 5
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5 out of 5
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Saved me pounds
9 May 2012
By JOETRIES
, Lancashire
" I envisaged a polished wood floor having to be taken up ,but 24 hours after applying this to the heating system the boiler pressure has not decreased. It was simple to use and would use it again if the need arises .[fingers crossed it doesn't] "
1 of 1 people found this review helpful.
Review 4 for Fernox Heating Leak Sealer Superconcentrate 290ml
Overall Rating: 
5 out of 5
5 out of 5
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5 out of 5
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5 out of 5
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5 out of 5
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5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating: 
5 out of 5
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Value: 
5 out of 5
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5 out of 5
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5 out of 5
magic potion
12 Jan 2011
By firebobby
, Midlands
" I recently had a new combi boiler installed and had other plumbing work completed to my old central heating system. This unfortunately induced a pressure loss in the system of 1 bar over a time period of approx. 1 day, necessitating constant topping up via the filling loop.
I purchased the fernox leak sealer and injected it via the filling loop using the kit included with the sealer. A very easy process taking less than ten minutes with a mastic gun (not supplied). That was over three weeks ago and their has been no pressure loss at all since. Basically, the sealer worked immediately. Brilliant. Hope this helps persuade future customers to purchase this miracle product.
"
4 of 4 people found this review helpful.
Review 5 for Fernox Heating Leak Sealer Superconcentrate 290ml
Overall Rating: 
5 out of 5
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5 out of 5
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Would you recommend this product? Yes
Overall Rating: 
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5 out of 5
Great problem solver
19 Apr 2010
By dustymonkey
, Fife
" After doing some DIY moving a couple of radiators about, I devoloped a leak in my heating system, as usaual under a floating floor which was tiled on top, no chance of getting to it without major ripping out. Combi boiler was losing 2.5 bar pressure in less than 8 hours, injectded the Fernox and pritty much instanly pressure was stable. Dead easy to use, a bit expensive, however compared to the alternative an absolute bargain. Highly recommend this to anyone with a similar problem. "
1 of 1 people found this review helpful.
Review 6 for Fernox Heating Leak Sealer Superconcentrate 290ml
Overall Rating: 
5 out of 5
5 out of 5
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4 out of 5
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Would you recommend this product? Yes
Overall Rating: 
5 out of 5
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Fernox Leak Sealer
14 Jan 2009
By Mediaman
, Sheffield
" This is a superb product. I applied this to my heating system which had a leak and was losing pressure after 14 days. After application it maintained pressure for over 2 years!
Fantastic.
"
1 of 1 people found this review helpful.
Review 7 for Fernox Heating Leak Sealer Superconcentrate 290ml
Overall Rating: 
5 out of 5
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5 out of 5
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4 out of 5
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Would you recommend this product? Yes
Overall Rating: 
5 out of 5
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5 out of 5
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5 out of 5
Didn't Think It Would Work
4 Jan 2009
By TryToDIYFirst
, Halifax
" Header tank on heating could always be heard "topping up". I added Fernox Heating Leak Sealer Superconcentrate 290ml to my system as a first option and the problem has been resolved.
I would recommend it to anyone with a similar problem. The tube needed a "gun" that I use for applying silicon repairs to apply it, which I was unaware of at time purchase.
Well worth the money !
"
Review 8 for Fernox Heating Leak Sealer Superconcentrate 290ml
Overall Rating: 
5 out of 5
5 out of 5
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3 out of 5
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3 out of 5
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4 out of 5
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Would you recommend this product? Yes
Overall Rating: 
5 out of 5
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4 out of 5
Good stuff
23 Oct 2008
By Vontrappe
, Cambridgeshire
" Used for the first time for three leaking towel radiators saved lots of time and did the job very well. Certainley would use again and probaly have a couple in the van. "
Review 9 for Fernox Heating Leak Sealer Superconcentrate 290ml
Overall Rating: 
4 out of 5
4 out of 5
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4 out of 5
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4 out of 5
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5 out of 5
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4 out of 5
4 out of 5
Would you recommend this product? Yes
Overall Rating: 
4 out of 5
4 out of 5
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4 out of 5
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5 out of 5
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Problem solver
11 Mar 2010
By grubbscrew
, South Devon
" What can I say, this stuff has been around for years and does what it says it does. It can be a bit messy if your injecting into a radiator so protect the carpet, best option if using on an unvented system is to introduce via filling loop. This will only seal minor weeps or leaks from joints or connections it wont seal unsoldered joints or corroded tubing. On systems with more than 10 rads I would definitely use two to ensure success and maybe introduce at opposite ends of the system. "