In older homes, hydronic systems are often still the original pipework and radiators, usually with a newer boiler. Proper inspection and maintenance is essential to keep this system fine tuned. Over decades, the valves, which are essential, are often never serviced. When old valves are used for temperature control (which they shouldn’t be!) they often start leaking at the valve stem. The water will trickle down the valve, onto the warm steel riser below the valve and rot the pipe out very quickly. The end result is a significant leak in your home.
The good news is that, in most cases, the radiator valve is repairable. The packing inside is compressed around the valve stem, sealing it off and preventing leaks. It’s always advisable, especially when people use their radiator valves, to periodically inspect them and have them repacked as required. If they’re no longer serviceable, replace the valve with a new one. This is a great opportunity to upgrade to a thermostatic radiator valve.