How do I stop a central heating radiator leaking without replacing it?
For a slow internal weep on joints you cannot easily reach, an in-system leak sealer like PC500 is added to the heating water and circulates to form a soft seal over the leak. Follow the dosing method for your system; a seal forms over about 24 hours, with full effect in one to six weeks.
Will it block the pump, valves or air vents?
No. PC500 is formulated to seal weeping joints without blocking the pump, valves or automatic air vents. It disperses readily and forms a soft seal only where water is escaping, so the rest of the system keeps circulating normally.
Is it safe for aluminium and multi-metal systems?
Yes. It is suitable for multi-metal systems, including those containing aluminium components such as modern boiler heat exchangers. It is compatible with the mix of metals and elastomer seals found in a typical sealed central heating system.
How do I add it to a sealed system?
Shake the bottle and add the full contents via the feed and expansion tank, or via a dosing point on a fully sealed system. Typically you tie up the ball valve, drain off some system water to make room, add PC500, then top up, vent and run the system.
How long does it take to work?
A soft seal begins to form over the first 24 hours, and the full sealing effect is usually achieved within one to six weeks of normal system running. Keeping the heating running helps the sealer circulate and find the leak.
Can I use it alongside an inhibitor?
PC500 is a leak sealer, not a corrosion inhibitor, so it does not replace your inhibitor. It is compatible with normal system water; once the leak is sealed, make sure the system still has the correct dose of inhibitor for ongoing protection against corrosion and scale.
Is it hazardous?
It is described as non-hazardous, non-flammable and non-irritant, with high stability and compatibility with system elastomers. As with any heating chemical, keep it away from children and avoid contact with eyes and skin.
When should I replace the joint instead of sealing it?
A leak sealer is ideal for minor weeps and inaccessible joints where stripping pipework would be costly. For a significant leak, a corroded radiator or a visibly failed fitting, a mechanical repair or replacement is the correct fix – sealer is best for small, hard-to-reach leaks.
