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Central Heating Leak Sealer

Central Heating Leak Sealer
Average Customer Rating:
4.533 out of 5
4.5
 out of 
5
(15 Reviews) 15
Open Ratings Snapshot
Rating Breakdown 15 reviews
5 stars
12
4 stars
1
3 stars
0
2 stars
2
1 star
0
13 of 15(87%)reviewers would recommend this product.
Customer Questions & Answers:
5 Questions | 6 Answers
Customer Reviews for Fernox Central Heating Leak Sealer F4 500ml
Review 1 for Fernox Central Heating Leak Sealer F4 500ml
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Excellent product
13 Jun 2016
By
, Pontefract
" Recommended by my plumber and did not disappoint, was loosing central heating pressure overnight, filled through magna filter and 4 days now and pressure has not budged so worth every penny. "
Review 2 for Fernox Central Heating Leak Sealer F4 500ml
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Brilliant
14 Jan 2016
By
, Rochdale
" Didn't think this would work or be easy to use, it was both, sealed my leaks, my combi boiler has now started holding pressure - don't think it's ever done that! "
7 of 9 people found this review helpful.
Review 3 for Fernox Central Heating Leak Sealer F4 500ml
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Does what it says ion the tin
2 Jan 2016
By
, Shropshire
" As a retired plumber with a back injury, i was not too keen to have to drain down my combo boiler system.
I had developed 3 leaks and was encountering pressure drops.
One from an iso valve gland, one from a lock shield valve and one from the boiler heating feed pipe.
I had never used F4 sealer before, and was a little reluctant. I isolated my bathroom towel rail, and removed the top bleed point fitting. I then used a hand siphon to remove just over half a litre of water. I then added the F4 and topped the towel rad back up to the brim. Bleed plug back in and valves re-opened. Less than 5 minutes to complete......DID it work ? Yep, i was well impressed no sign of a leak anywhere after a couple of weeks and pressure is maintained. Recommended.
"
23 of 23 people found this review helpful.
Review 4 for Fernox Central Heating Leak Sealer F4 500ml
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
4 out of 5
4 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
4 out of 5
4 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Great product
31 May 2015
By
, Halifax
" 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 "
15 of 15 people found this review helpful.
Review 5 for Fernox Central Heating Leak Sealer F4 500ml
Overall Rating
5 out of 5
5 out of 5
Value
3 out of 5
3 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating
5 out of 5
5 out of 5
Value
3 out of 5
3 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
top quality
29 Mar 2015
By
, blackpool
" overpriced but the best for the job and accepted on all my guarantee requirements for certificates "
2 of 10 people found this review helpful.
Review 6 for Fernox Central Heating Leak Sealer F4 500ml
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Does Exactly What It Is Suppos
23 Jul 2013
By
, Fife
" I have an oldish CH system (about 40 years old) and have been bothered for ages by a variety of hard-to-trace weeps. I recently had a new pressurised boiler fitted and the system was losing pressure at the rate of around 0.1 - 0.2 bar per week (more than 0.5 litres per week).I added the fernox and the system has lost no noticeable pressure over a period of a month. Better than expected result! "
17 of 17 people found this review helpful.
Review 7 for Fernox Central Heating Leak Sealer F4 500ml
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Does exactly what it says !
31 Jan 2013
By
, Wirral
" Having had a fairly bad leak from a large vertical radiator (poorly welded joints) I decided to give Fernox F4 a go by adding the whole bottle to my central heating header tank in my loft...and then draining a few pints off from one of my radiators...to get the stuff into the system & circulating. Amaizingly after only 2 hours of running the central heating...the leak had stopped completely !. Fantastic product.- does exactly what it says !. "
5 of 8 people found this review helpful.
Review 8 for Fernox Central Heating Leak Sealer F4 500ml
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
it did the trick
9 Apr 2012
By
, Holyhead
" my central heating system had suffered from a persistent, inaccessible, weeping leak for several months. A large plumber's bill for pipework replacement was feared. A friend in the know recommended Fernox F4. Within 24 hours the leak had stopped completely. The directions for application on the container were easily followed and are spelled out slightly more specifically on the Fernox web-site. Problem solved. "
7 of 7 people found this review helpful.
Review 9 for Fernox Central Heating Leak Sealer F4 500ml
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
4 out of 5
4 out of 5
Performance
5 out of 5
5 out of 5
Reliability
4 out of 5
4 out of 5
Would you recommend this product? Yes
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
4 out of 5
4 out of 5
Performance
5 out of 5
5 out of 5
Reliability
4 out of 5
4 out of 5
Problem solved
12 Feb 2011
By
, Gwent
" After trying and failing for almost a year to find leak causing pressure drop - and topping up every few days , I put Fernox into the system via radiator using ' no nonsence filling kit' - easily done. Since then after 3 or 4 weeks no pressure loss at all.
So far -so good I would recommend this to anyone.
"
8 of 8 people found this review helpful.
Review 10 for Fernox Central Heating Leak Sealer F4 500ml
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Does what it is supposed to do
2 Dec 2009
By
, Milton Keynes
" Recommended by a plumber mate. Talked me through doing a partial drain down of my system and poured this in, a day or so later the leaky radiator valve has been sorted out. Does the job, what more can I say. Have patience, it didn't work straight off but 24 hours or so later and having run the central heating a couple of times seems to do the job. "
4 of 4 people found this review helpful.
Review 11 for Fernox Central Heating Leak Sealer F4 500ml
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
4 out of 5
4 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
4 out of 5
4 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Great product
27 Nov 2009
By
, Weston-super-Mare
" Both isolation valves on my Gloworm Combi were leaking. Expensive and difficult to replace. I was disappointed at first but after 48 hours the drips stopped. No pressure loss over 1 year later. Recommended. "
4 of 4 people found this review helpful.
Review 12 for Fernox Central Heating Leak Sealer F4 500ml
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating
5 out of 5
5 out of 5
Value
5 out of 5
5 out of 5
Features
5 out of 5
5 out of 5
Performance
5 out of 5
5 out of 5
Reliability
5 out of 5
5 out of 5
It actually Works
9 Mar 2009
By
, London
" I had a leaking ball valve which was leaking through the open/ close screw and it was very dificult to get to to change it so i gave this stuff ago and it worked a treat. "
2 of 2 people found this review helpful.
Review 13 for Fernox Central Heating Leak Sealer F4 500ml
Overall Rating
4 out of 5
4 out of 5
Value
3 out of 5
3 out of 5
Features
3 out of 5
3 out of 5
Performance
4 out of 5
4 out of 5
Reliability
4 out of 5
4 out of 5
Would you recommend this product? Yes
Overall Rating
4 out of 5
4 out of 5
Value
3 out of 5
3 out of 5
Features
3 out of 5
3 out of 5
Performance
4 out of 5
4 out of 5
Reliability
4 out of 5
4 out of 5
Leak sealer
17 Jan 2015
By
, Birmingham
" Again screw fix has come up with the goods,can not fault the quality of service and value for money . "
Review 14 for Fernox Central Heating Leak Sealer F4 500ml
Overall Rating
2 out of 5
2 out of 5
Value
2 out of 5
2 out of 5
Features
2 out of 5
2 out of 5
Performance
1 out of 5
1 out of 5
Reliability
1 out of 5
1 out of 5
Would you recommend this product? No
Overall Rating
2 out of 5
2 out of 5
Value
2 out of 5
2 out of 5
Features
2 out of 5
2 out of 5
Performance
1 out of 5
1 out of 5
Reliability
1 out of 5
1 out of 5
Unable to sort leak
12 Nov 2015
By
, Jarrow
" The boiler engineer has put my boiler pressure vessel on test,but believes I have a system leak.
Tried a 1litre bottle of a competitor's leak sealer and it didn't work.Thought I'd try a 0.5 litre bottle of Fernox several day's ago.This hasn't worked either so I haven't found it to be the "magic bullet" that others speak of.Will still have to investigate under the floorboards!
"
Review 15 for Fernox Central Heating Leak Sealer F4 500ml
Overall Rating
2 out of 5
2 out of 5
Value
1 out of 5
1 out of 5
Features
2 out of 5
2 out of 5
Performance
1 out of 5
1 out of 5
Reliability
1 out of 5
1 out of 5
Would you recommend this product? No
Overall Rating
2 out of 5
2 out of 5
Value
1 out of 5
1 out of 5
Features
2 out of 5
2 out of 5
Performance
1 out of 5
1 out of 5
Reliability
1 out of 5
1 out of 5
Doesn't do the job
14 Aug 2015
By
, Southeast London
" 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. "
0 of 5 people found this review helpful.