Power flushing and radiatorsin Harrow, for a heating systemthat heats every room

Most heating systems use steel radiators and copper or plastic pipework. Over time, oxygen in the water causes corrosion inside the radiators, producing a black iron oxide sludge called magnetite. It settles at the bottom of radiators and is carried around the system, collecting in the boiler's heat exchanger, the pump and valves.

Signs of sludge include radiators that are warm at the top but cold at the bottom, very dark water when you bleed a radiator, a noisy boiler, a pump that fails repeatedly and a system that takes a long time to warm up.

After a power flush, adding the correct dose of inhibitor slows corrosion down. A magnetic filter fitted on the return pipe to the boiler captures magnetite before it reaches the boiler and can be cleaned during the annual service.

When adding or replacing radiators, the heat output needs to suit the size of the room, its windows and outside walls. A radiator that looks right but is undersized will leave the room cold. We size new radiators so each room reaches a comfortable temperature.

A power flush is carried out radiator by radiator. Each one is isolated in turn while high-flow water and cleaning chemicals are pushed through it, loosening sludge and flushing it out of the system. Radiators can be tapped or agitated to break up stubborn deposits. Once the water runs clear, the system is refilled, treated with inhibitor and checked for even heat across every room.

If your radiators are very old, badly corroded or already leaking, replacing them can be better value than flushing them. We tell you honestly which option makes more sense for your system.