Central Heating Leak Sealer
Rapid internal sealing solution for weeping joints & micro-leaks
Vitcas Central Heating Leak Sealer is a high-performance additive designed to seal inaccessible internal leaks in sealed or open-vented fully indirect central heating systems. It offers a non-invasive repair for weeping joints, pinhole leaks, and micro-fractures, allowing you to address issues without draining or disassembling the system.
Formulated for safe use with all standard heating system components, it is compatible with aluminium, copper, brass, steel, plastic feed tanks, and microbore pipework. The product is chemically activated only at the site of air ingress or pressure loss, forming a localised seal that does not block pumps or narrow channels. It integrates seamlessly with all other Vitcas® central heating products, making it ideal for both emergency repairs and preventative maintenance.
Boiler leak control for sealed heating systems
This solution is ideal for systems experiencing minor but persistent pressure loss. By targeting the leak site directly, the product stabilises system pressure, restores flow balance, and reduces the risk of long-term damage caused by untreated leaks - without interrupting operation.
Technical benefits for central heating systems
- Seals internal micro-leaks and weeping joints
- No need to flush or drain the system
- Safe for all common heating materials - including aluminium and plastics
- Compatible with plastic feed tanks and microbore pipework
- Remains in the system for ongoing protection
- Fully compatible with Vitcas® Inhibitor, Cleaner, and Boiler Noise Silencer
- Suitable for commercial, domestic, and light industrial heating systems

Live system integration without drainage or downtime
- Switch off the central heating system and allow it to cool to a safe temperature.
- Shake the container thoroughly to ensure the active ingredients are evenly dispersed.
- Locate a suitable dosing point - typically a radiator bleed valve, system filling loop, or dosing pot.
- Inject the leak sealer using a caulking gun or dosing vessel, depending on packaging format.
- Restore system pressure (if required) and turn the heating system back on.
- Allow normal circulation for at least 1 hour. For heavily scaled or slow systems, circulate for up to 24 hours.
- Leave the product in the system permanently - no flushing or water replacement is required.
Note: For use in fully indirect systems only. Not suitable for primatic (single-feed) cylinders.