The Sentinel Leak Sealer (MPN ILS) is a leave-in additive for sealing minor leaks and weeping joints in all types of indirect central heating systems, including those containing aluminium components. Once added, it forms a soft seal over the leaking area, normally within 24 hours depending on leak rate and system temperature, without causing blockages elsewhere in the system.
~24 Hours
Typical Seal Time
Up to 10 Radiators
Coverage
Elastomers
Compatible With
Compatible With Existing Treatment
Sentinel Leak Sealer is compatible with other Sentinel products that may already be present in the system, so it can generally be added without needing to drain and refill.
Dosage Depends on System Size
1 litre treats a typical domestic system of up to 10 radiators. Larger systems should be dosed with 2 litres. This product will not seal significant leaks or resolve mechanical failures - it is intended for minor weeping joints and pinhole leaks only.
Post-Dosing Operation
After dosing, the system should be operated normally for at least 15 minutes, as heat is beneficial to the sealing process.
Effective on Minor Leaks
Designed to seal weeping joints and pinhole leaks that are too small to justify a full repair callout, extending the useful life of ageing joints and fittings.
Won't Cause Blockages
Formulated to be readily dispersible, meaning it will not build up and block narrow pipework, radiator valves, or heat exchangers elsewhere in the system.
Broad Metal Compatibility
Suitable for use in all types of indirect central heating system, including those with aluminium components, and is compatible with elastomers such as seals and gaskets.
Compatible with Other Treatments
Can be used alongside existing Sentinel inhibitor and cleaner products already circulating in the system, without needing to drain down first.
Non-Toxic, Non-Irritant
Formulated to be non-toxic and non-irritant, making it straightforward and low-risk to handle and dose on site.
Rapid-Dose Format Available
Where faster dosing is needed, Sentinel also offers this product in a Rapid-Dose format for quicker application directly into the system.
| Product Identity |
| Manufacturer |
Sentinel (Sentinel Performance Solutions) |
| Product Name |
Sentinel Leak Sealer |
| MPN |
ILS |
| Application |
| Use Case |
Sealing minor leaks and weeping joints |
| System Types |
All types of indirect central heating system |
| Typical Sealing Time |
Approx. 24 hours (leak-rate and temperature dependent) |
| Dosage |
| Standard Dose |
1 litre per typical domestic system (up to 10 radiators) |
| Larger Systems |
2 litres |
| Post-Dose Operation |
Run system normally for minimum 15 minutes |
| Compatibility |
| Metals |
All metals including aluminium |
| Elastomers |
Compatible with elastomers (seals, gaskets) |
| Other Sentinel Products |
Compatible with existing Sentinel inhibitors and cleaners |
| Quality System |
Manufactured under ISO 9001 |
What size leaks will this product seal?
Sentinel Leak Sealer is designed for minor leaks and weeping joints - not significant leaks, mechanical failures, or large pipe splits, which require a physical repair.
How long does it take to seal a leak?
A soft seal typically forms within 24 hours, though this depends on the rate of the leak and the system's operating temperature.
Will it block my radiators or pipework?
No. The formulation is readily dispersible and is specifically designed not to cause blockages elsewhere in the system.
How much do I need for my system?
1 litre treats a typical domestic system of up to 10 radiators. Larger systems should be dosed with 2 litres.
Can I use this alongside my existing inhibitor?
Yes, Sentinel Leak Sealer is compatible with other Sentinel products already circulating in the system.
What should I do after dosing?
Operate the system normally for at least 15 minutes after dosing, since heat assists the sealing process.
