Heating Tools

A heating system pressure tester connects to a radiator valve or service port and applies controlled air pressure to check for leaks before filling or after repair. The gauge reads in bar; residential systems typically run 1–1.5 bar cold, light commercial slightly higher. Testers with a hand pump and bleed valve let you add pressure in small increments and release it gradually — useful when isolating a leak to one zone or checking new pipework before commissioning. Some models include adaptors for different valve types; check you have the right fitting for the system you're working on.

Pressure testing catches slow leaks that won't show under mains water pressure but cause boiler lockouts and topping-up cycles once the system is live. If the gauge holds steady for ten minutes, the system is tight. A slow drop points to a weeping joint, a corroded rad tail, or a pinhole in buried pipe. Testing before you fill saves time and mess — fixing a leak under pressure means draining down, which adds an hour to the job and wastes inhibitor.

Most testers ship with a carry case and a set of common adaptors. Check the hose length if you're working on multi-storey systems; a short hose forces you to work at the test point rather than watching the gauge from the boiler. Gauges should be easy to read in low light — large dials with clear increments matter more than digital precision for this kind of work.