Top 8 Radiator Leak sealant UK – Sealers

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1. CosWarm

Stops Minor Leaks & Weeps, Boiler Leak Repair & Sealant, Fixes Pressure Loss & Leaking Pipes, CosWarm CW4 Central Heating Leak Sealer, Treats Up To 18 Radiators, Stops Leak

CosWarm - Stops small leaks & fixes pressure loss: cw4 leak sealer seals all the small and inaccessible leaks, thus saving time and money in draining down and repairing cost. Safe to use around people, chemical formulas. Convenience at its best: our leak sealer and stopper makes minor repairs in the boiler a breeze.

Harmless for metals: there are many leak sealant chemicals that are not friendly when they come into contact with metals. Cw4 leak sealer liquid is suitable for use with all the metals and materials, including steel, ferrous metals, copper and aluminium. Safe for you, the boilers & the environment: our non-toxic radiator leak sealer is a safer alternative compared to other toxic, it won’t harm Mother Nature either. As it is biodegradable, the environment and your heating systems.

Our boiler leak sealant also helps in fixing pressure loss due to minor leaks from central heating systems. It is easy to use, just pour it in the system according to the instructions and let it work. Super concentrated formula: our boiler and central heating system leak stopper can treat up to 18 single radiators, i. E. A 150-litre system. It does not interfere with the working of your central heating systems and you won’t have to shut down the systems before or while using it.
Weight0.45 kg (1 Pounds)
Part NumberCosWarmCW4

2. Evo-Stik

Instant Repairs for Pipes, Radiators, Waterproof, EVO-STIK Plumber's Mait Quick Leak Repair Putty, 50g, Tanks & Cylinders

Evo-Stik - Strong, waterproof and fast setting epoxy putty designed for long lasting emergency plumbing repairs to leaking pipes, radiators, tanks and cylinders. Contents: 1x evo-stik plumber's Mait Quick Leak Repair Putty, 50g. Easy to apply - when dried it can be drilled, sanded, machined and painted. Can be applied to damp or wet surfaces, Waterproof and chemical resistant, Resists temperatures up to +150°C. Ideal for bonding to copper, fibre glass, brass, steel, aluminium, acrylic and porcelain.
Height20.3 cm (7.99 Inches)
Length11.4 cm (4.49 Inches)
Weight0.05 kg (0.11 Pounds)
Width3 cm (1.18 Inches)
Part Number30812665
WarrantyNo guarantee.

3. Unknown

Corgi TRIPCON5-C Concentrated Central Heating Leak Sealer, Clear

Unknown - Non-acidic, non-caustic - safe to handle. To seal inaccessible leaks and weeping joints. Reduces pressure loss in sealed systems & does not cause blockages in circulator pumps or air vents. Controls scale and maintains boiler efficiency. Concentrated 500ml treats up to 10 radiators - a typical central heating system.
Height18.5 cm (7.28 Inches)
Length9 cm (3.54 Inches)
Width4.5 cm (1.77 Inches)
Part NumberTRIPCON5-C
WarrantyNo guarantee.

4. Polar Specialist Coatings

Polar S1 Superior Leak Sealer Clear Spray – Tough Waterproof Sealant – Instant Repair – 400ml

Polar Specialist Coatings - Excellent coverage - easy application with an excellent coverage, an ideal solution for quick repairs. Superior leak sealer - polar S1 provides an instant seal with an excellent resistance to weathering with a high covering power. Available in White, Black and Grey. Multi-purpose use - polar s1 leak sealer can be applied to most rigid surfaces including metal, wood, plastics and ceramics. Tough seal - the sealant uses a rubberised protective formula to provide a flexible yet tough seal.
BrandPolar Specialist Coatings
ManufacturerPolar Protective Products
Height18 cm (7.09 Inches)
Length18 cm (7.09 Inches)
Width7 cm (2.76 Inches)

5. Fernox

Fernox 61016 50ml LS-X External Leak Sealer

Fernox - Ideal for use on compression joints and screwed fittings. External leak Sealer and Jointing Compound. Ready -to- use, no mixing. Wras approved product - completely safe to use with drinking water. Never sets rock hard, joints can easily be undone.
Weight0.07 kg (0.16 Pounds)
Part Number61016


Fills, 400ml, JENOLITE Stop Leak Sealer Spray, Seals & Stops Leaks, CLEAR, Waterproof sealant

JENOLITE - Suitable for the quick repair of guttering, windows, drains, pipework, roofs and other leaking areas. Waterproof seal stops leaks and drips fast. Remains flexible & pliable for years after use. Completely waterproof and corrosion resistant surface. Dries to create a waterproof seal.
Part Number89183

7. Fernox

Yellow, Fernox LS-X External Leak Sealer and Jointing Compound

Fernox - Never sets rock hard; joints can easily be undone. Wras approved- completely safe to use with drinking water. Ideal for use on compression joints and screwed fittings. Ready to use, no mixing. Jointing compound and external leak.
Weight0.06 kg (0.13 Pounds)
Part NumberLS-X

8. Fernox

Fernox 56603 Leak Sealer

Fernox - Compatible with all metals and materials commonly used in central heating systems. Plugs small internal weeps and leaks in central heating systems. Ideal for reducing pressure loss from sealed systems. Saves time and money on draining down and repairing. Treats 100l system or up to 10 single radiators.
Height6.8 cm (2.68 Inches)
Length21 cm (8.27 Inches)
Weight0.58 kg (1.28 Pounds)
Width9.8 cm (3.86 Inches)
Part Number56603