Flomasta Central Heating Leak Sealer 500ml Product Code: 6774R

Internal leak sealer for small, inaccessible leaks and weeping joints which reduce system pressure. Effective within 24 hours. Suitable for mixed metal systems, including aluminium. Does not cause blockages in circulator pumps or air vents. 500ml treats 100Ltr.


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Additional Information
Technical Specification
  • Brand : Flomasta
  • Product Type : Central Heating Leak Sealer
  • Volume : 500 ml
  • Model No : 0647
  • Pack Size : 1
  • Manufacturer Guarantee : 1 Year Guarantee
  • Pieces in Pack/Case : 1
Product Contents
Delivery & Returns


Standard delivery service up to 3 working days: €8.95

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€9.75 Incl. 23% VAT

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Flomasta Central Heating Leak Sealer 500ml is rated 4.8 out of 5 by 19.
Rated 5 out of 5 by from Good value for money Does the job. Just empty one radiator in the bathroom preferably. Pour this in and after a few days should be. Fine.
Date published: 2019-04-02
Rated 5 out of 5 by from Leak sealer Excellent product, really easy to open and pour. Very impressed.
Date published: 2019-03-29
Rated 5 out of 5 by from DIY Easy to install, day 2 and pressure on boiler seems to be stable, only time will tell hence the 4 stars on performance and reliability.
Date published: 2019-01-16
Rated 5 out of 5 by from time saver great product no need to go for the big brands this works
Date published: 2019-01-15
Rated 5 out of 5 by from IT WORKED FOR ME The pressure kept dropping on the boiler over several weeks and then it tripped out on 'low boiler water pressure' I checked round all radiators & pipe work I could see but NO leaks were apparent. I decided that the leak was some were that it could not be seen in the central heating pipe work. I isolated the boiler and turned off the two isolation valves for the magnetic filter. Then drained the filter and cleaned it. I filled it with the leak sealer after shaking the bottle. Then reassembled the filter. The system has held its pressure for longer than it did before.
Date published: 2018-12-10
Rated 5 out of 5 by from does what it says have used this before easy to used and it works highly reccomended
Date published: 2018-11-14
Rated 5 out of 5 by from No more leaks Had annoying leak on a radiator in an old house and didn’t really want to mess about with existing valve joints so added this little bottle of fun to the system via a bathroom towel rail, an hour or two later no weaping and pressure holding up well. Recommended
Date published: 2018-10-08
Rated 5 out of 5 by from Great Sealer Had a persistent weep on the central heating. This product is easy to apply: just pour into the header tank and draw off enough water to ensure the product is taken into circulation. Although the instructions said to leave the heating on for a longer period, the weep was stoppped within an hour of starting . Excellent product, and very competitively priced. Only just applied so cannot say how long it will last, hence only average rating for reliability.
Date published: 2018-09-07
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