Flomasta 0647 Central Heating Leak Sealer 500ml (6774R)

£ 7.98INC VAT

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Flomasta 0647 Central Heating Leak Sealer 500ml (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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Flomasta 0647 Central Heating Leak Sealer 500ml is rated 4.8 out of 5 by 43.
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Rated 5 out of 5 by from Good for small leaks. I recently used this for a central heating system that was losing pressure from 1bar to 0bar in a 24 hour period. I added this sealer to the system, pressurised back up to 1bar and turned the heating on for 2 hours. The next morning the pressure was still on 1bar and has been ever since. Would recommend to anyone in a similar situation.
Date published: 2021-04-30
Rated 5 out of 5 by from Miracle cure in a bottle I have to say I was sceptical of using leak sealer? I had a very difficult to find pressure loss in a sealed heating system in a park home. Old boy couldn't be without heating, and as a last resort after crawling under the caravan looking for leaks, I poured a bottle 500ml into a radiator which I had drained previously. Within minutes the pressure guage was holding steady? There must have been a small leak under the floor, it was losing pressure over 24hr period, it had expansion vessel and prv replaced. All I can say is I was well impressed and have a happy customer!! I always have a bottle in my van!
Date published: 2021-04-13
Rated 5 out of 5 by from Amazing stuff This product saved the day, a connection to my CH boiler was weeping water and the connection was really inaccessible, I added this to my CH system and within 2 hours the leak had completely stopped. It certainly does what it states on the bottle.
Date published: 2021-04-11
Rated 5 out of 5 by from It works I have had a problem for a few years with my boiler losing pressure very slowly, put this in the system and it's OK now.
Date published: 2021-04-06
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How does this sealer work?

Does it cure on contact with air, or?
Asked by: soother
Hello soother, It does not cure with air (like automotive Radweld) - it works by altering the surface tension of water - so works best in a capillary leak. It won’t block the pump or valves. Thank you for using Q&A
Answered by: Cwalm
Date published: 2020-12-22

Will this product seal a leak in a combi primary or condensing heat exchanger?

My combi boiler pressure drops from 1 bar to zero in around 5 days. I have fully checked the rest of the system, & the leak has to be a pinhole crack or split in either the primary or condensing heat exchanger. Will this product cure it?
Asked by: soother
Leak Sealer is good at sealing problems that lead to pressure drop - but works best at sealing capillary leaks because the product alters the surface tension of the system water. A capillary leak would be a join where the solder had not fully run around the pipe. Holes can be more challenging. It’s a cheap solution to a potentially expensive problem - you will quickly find out if it works - if it doesn’t it will not block seals or valves. Don’t be tempted to over use. Just one bottle per 100L or 10 rads is sufficient.
Answered by: Water Treatment Expert
Date published: 2021-02-14

How often can you use this product? I put a bottle in a year ago and have a slight leak again now.

Asked by: Kugjydy
As long as you don’t use it more frequently than annually it shouldn’t be a problem. If repeat application doesn’t work it’s likely that you have developed a mechanical fault requiring further investigation.
Answered by: Water Treatment Expert
Date published: 2021-01-14

Can this product be used on an Gravity fed, OPEN VENTED system?

Asked by: Anonymous
Yes the product can be used on open vented and sealed pressurised systems. We would recommend that you introduce it directly into circuit (via a radiator or filter for example) as it can take up to six weeks to reach equilibrium if introduced via the feed and expansion tank - which would be far to long to wait to seal your leak.
Answered by: Water Treatment Expert
Date published: 2021-01-02

Replace after draining and refilling system?

I have recently used this and it has worked a treat - thanks. My question - if I now need to subsequently drain and refill the system, will I need to add this leak sealer again or can I assume the previous application has sealed the leak?
Asked by: Dunder101
Hello, Thank you for your enquiry. This sealer is a temporary fix and we would advise that the leak be repaired properly before refilling again and would not solely rely on the leak sealer. Hope that helps. Thank you for using Q&A. MH
Answered by: Screwfix778
Date published: 2020-03-07
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Specification
Brand Flomasta
Label Info 2: Hazard Statements EUH 210 Safety data sheet available on request.
Label Info 3: Precautionary Statements P102 Keep out of reach of children.P501 Dispose of contents/container to …
Manufacturer Guarantee 1 Year Guarantee
Model No 0647
Pack Size 1
Pieces in Pack/Case 1
Product Type Central Heating Leak Sealer
Volume 500 ml

Downloads

Safety Data Sheet (COSHH)