Cleaning a central heating system removes contaminants which would otherwise form a harmful sludge in your heating system which will not only reduce the efficiency of the system, but also create noise and potentially reduce the useful life of your appliance.
There are a variety of contaminants that can build up including residue from compounds used during pipework installation, grease, oxides produced by corrosion, bacteria and, in hard water areas, limescale too.
If you are replacing your boiler then a system clean is essential prior to installation of the new appliance. If this is not carried out there is a serious risk that your new boiler will be contaminated with damaging sludge and debris that was present in old, uncleared pipework.
You may hear system cleaning referred to as “power flushing”, a method that uses a specialist pump during the cleaning process. However, mains pressure and pumped gravity cleaning methods are also acceptable.