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Fernox Central Heating Leak Sealer F4 500ml

Product Code: 45902

Used throughout domestic heating systems for sealing small, inaccessible leaks. Does not block air vents and pumps.

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Rated 2 out of 5 by Doesn't do the job Have a leak under the concrete floor so decided to try this based on the reviews people have written. To start with it wasn't easy to pour into the radiator. Once done and left the heating on for 30 mins and turned off for 24 hours for moment of truth.... Didn't work at all. I was so disappointed. Even if it has worked still I think it's over priced for the quantity you get, at least they could have thrown the gun to pour the liquid into the rad to make the price worth. Didn't work for me hence the low scoring. 14 Aug 2015
Rated 5 out of 5 by Great product Apart from being a bit tricky to get into the system, this product is amazing!!! I was losing pressure on my combi boiler all the time, not anymore. After 2 days pressure has stabilised and held, very impressed 31 May 2015
Rated 5 out of 5 by top quality overpriced but the best for the job and accepted on all my guarantee requirements for certificates 29 Mar 2015
Rated 4 out of 5 by Leak sealer Again screw fix has come up with the goods,can not fault the quality of service and value for money . 17 Jan 2015
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10 Sep 2015
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Brand Fernox
Colour Green
Manufacturer Guarantee 10 years
Model No F4
Pack Size 1
Product Type Central Heating Leak Sealer
Sealant Adhesive Volume 500 ml
Total Product Weight 572 kg