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B&Q£24.99Visit shop B&Q - Cw4 Central Heating Leak SealerTreats Up To 18 RadiatorsStops Leaks & Pressure Loss
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The CosWarm CW4 Central Heating Leak Sealer is an essential maintenance product for homeowners and heating technicians looking to resolve persistent pressure drops in central heating systems. Designed for systems with up to 18 single radiators or a 150-litre capacity, it effectively seals inaccessible leaks in boilers, pipework, and radiators without the need for manual repairs. While it is highly efficient at patching minor weeps, it is important to note that it is not intended to repair major structural pipe failures or burst connections.
| Model Part Number | CW4 |
|---|---|
| Brand | CosWarm |
Yes, the CW4 is compatible with standard underfloor heating circuits.
No, the product is designed to be added to the existing water in the system.
The formula is non-toxic and compatible with standard heating system metals, so it will not harm boilers or pump components.
Most micro-leaks are sealed within 24 to 48 hours of circulation.
Yes, it provides a long-term seal for small leaks and weeps.
The leak may be too large for the sealant to bridge; inspect the system for visible signs of wet joints or structural damage.
Ensure the system is properly bled of air and that the pump is operating at the correct speed after adding the product.
To apply the CosWarm CW4, you do not need to shut down your heating system. Simply isolate a radiator or use a dedicated system filter to inject the liquid directly into the pipework. This product is engineered to remain within the heating fluid and does not require flushing unless you are performing a full system overhaul. It is compatible with all standard inhibitors and antifreeze solutions, making it an excellent addition to annual maintenance routines. Keep the container tightly sealed and stored in a cool, dry place away from direct sunlight when not in use.
