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Fernox Central Heating Leak Sealer 400ml
B
bass-heating-spares-ltd (1507)
99.6% positive Feedback
Price:
£17.90
Free postage
Returns:
14 days return. Buyer pays for return postage. If you use an eBay delivery label, it will be deducted from your refund amount.
Condition:
Fernox Express F4 400ml Central Heating Leak Sealer F4 comes with all 3 nozzles Brand new 30 seconds and it's in your system Treats 130 litres 16 radiators 250m2 under floor Stops small leaks All instructions are on the can
- Buy it nowFernox Express F4 400ml Central Heating Leak Sealer F4 comes with all 3 nozzles
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About this product
Product Identifiers
BrandFernox
MPN62422
EAN5014551624221
eBay Product ID (ePID)28032632367
Product Key Features
Power SourceGas/Petrol
TypeCombi Boiler
Heating SystemBoiler
Mounting LocationWall, Under Sink, Tabletop
All listings for this product
Ratings and reviews
Most relevant reviews
- 22 Dec, 2021
Need Internet to find how to use
Great product to seal central heating, if you suffer from a very small leak. Pressure now good on the boiler. Lacks instructions, which you probably need to use the Internet, if you haven't used it before. But it's very easy to use, once you know how.Verified purchase: YesCondition: New
- 27 Mar, 2025
I’ve been having to top up my boiler eve...
I’ve been having to top up my boiler every few days because of a small leak and thought I would give this a go fully expecting it not to work. Takes a little working out how to get it into the system I did it through a radiator, and so far it’s worked a treat.Verified purchase: YesCondition: New
- 03 Mar, 2025
Have used this to cure a slight leak in ...
Have used this to cure a slight leak in a pressurised central heating system worked for 3 years re dosing again so hopefully it will work for another couple of yearsVerified purchase: YesCondition: New
- 25 Mar, 2020
So far so good
Used to have to top up my heating system weekly, but was unable to find any visible leaks. 2 weeks after adding F4 pressure has not dropped.Verified purchase: YesCondition: New
- 11 Jan, 2025
It gets the job done.
It is designed to seal micro leaks in central heating systems and it seems to work well.Verified purchase: YesCondition: New
- 07 May, 2021
Does what it says on the tin!
I was disappointed that I couldn't use it via the filling loop, I have been able to do that in the past. In the end I applied the sealer via the radiator bleed valve opening, which was a bit messy when I removed the can from the radiator, so be prepared! Having said that, the product has done a brilliant job!Verified purchase: YesCondition: New
- 13 May, 2024
We found the leak! But will still be putting this into our rather old system.
We found the leak! But will still be putting this into our rather old system.Verified purchase: YesCondition: New
- 25 Mar, 2020
Got my boiler working in less than 15 minutes
Worked well for me where I was weekly loosing system pressure and having to top-up with water via the filling loop to regain the correct pressure to keep the boiler working. I consider the price of Fernox Express F4 Leak Sealer 400ml very reasonable, especially when compared with a boiler engineer call out fee and/or the cost and inconvenience of lifting the floor boards to find a seep.Verified purchase: YesCondition: New
- 26 Jan, 2024
Have not used it yet
Have not used as yet. One thing though is the complete lack of any instructions & you need to look on the internet to find out the best way to use it which is annoyingVerified purchase: YesCondition: New
- 10 Feb, 2021
Really easy to use
Very easy to use and works great productVerified purchase: YesCondition: New
