Chemical cleaning of a heating system

Within a central heating system we generally have a boiler, hot water cylinder, pump, valves, expansion vessel, pipework etc made from a mixture of metals and other materials.

Heating and mixing the system contents - water, paste and flux residue - creates a chemical reaction that produces scale, black sludge and hydrogen gas. Eventually this can cause cold spots in a radiator and sludge can even cause blockages.

All this will reduce the heat transfer of the radiators and efficiency of the boiler but with a chemical cleaning product (Sentinel) this can be dealt with.

Ideally, before undertaking a boiler change on an installation the system should be cleaned. This will prolong the life of the new boiler and is a requirement for the manufacturer's guarantee. Similarly, prior to commissioning a new installation the system should be chemically flushed and have a chemical inhibitor added to preserve it. This process will help the efficiency of the system, thus reducing energy consumption.

Powerflushing is a mechanical means to speed up the cleaning process.

When choosing the locations for new radiators, try to place them beneath a window. This takes advantage of the convection currents available, thus increasing the overall efficiency of the heating system.