Power flushing a central heating system

How do I know if my heating system needs flushing?

There are several signs that can indicate when your central heating system is in need of a power flush or a chemical flush.

If you are having problems with poor performance and blockages affecting your central heating system’s performance it is often caused by corrosion and a build-up of deposits in the heating system pipework and radiators.

Spot the signs

that your heating needs a flush

  • Noises from the boiler, pipes and radiators

  • Radiators do not heat-up properly

  • Cold spots on radiators

  • Radiators often need bleeding

  • Dirty water in the heating system

  • Deposits in pumps

  • Corroded and leaking radiators

  • Regular faults with pumps, valves and other parts

What is a power flush?

A power flush is a pressurised chemical flush of the pipework and radiators of your central heating system and in some case the boiler. It designed to clean and clear the system by removing the build-up of ‘magnetite’ (a sludge made up fragments of rust from corroded metal, dirt and limescale). Magnetite occurs because of the combination of metal, air and water which over time which causes  the degradation of the metal by corrosion. When there is a build-up of magnetite it usually causes blockages in the system. As the system becomes blocked your heating system struggles to perform efficiently. If left unchecked this can cause significant damage to your boiler system by damaging the heat exchanges.

Chemical Flushing

An alternative to a power flush

There are circumstances where it may not be advisable to have a power flush of your central heating system. This may be the case if the pipework, the radiators and/ or their valves are old or rusty, as performing a power flush could lead to leakages. In these circumstances a chemical flush may be performed instead. This where the system is flushed without the pump machine.

Power flushing central heating

Performing A Power Flush On Your Heating System

To flush your central heating system, we connect a power flushing machine to the system and pump a combination of water and cleaning chemicals through the pipework and radiators. As the solution works its way through the system it breaks down and clears the magnetite and dirt so that it may flow out of the system and into a tank. This process may be performed a few times to ensure that the system is properly cleaned and flowing freely.

Once the flush is completed, the system can then be refilled with water and an additive known as an inhibitor to help protect your heating from the future build-ups of magnetite.

Power Flushing New Boiler Installations

Often a requirement of a manufacturers warranty

It is often part of the terms and conditions of a boiler manufacturer’s warranty requirements that the central heating system has a power flush as part of the installation. This is to protect the boiler and ensure that the heating system pipework is clean and clear of dirt and debris caused by corrosion.

Magna Clean Units

Fitting Magnaclean Units

Preventing further problems

After a new boiler installation and/or a power flush has been completed, we would advise fitting a Magnaclean unit. These units are designed to help keep the heating system clean and avoid the build-up of corrosive particles known as magnetite, which cause blockages and can damage the heat exchangers of your boiler system.

Contact Us

If the symptoms we have described sound like your heating system, please contact us to arrange a visit by one our expert Gas Safe Registered heating engineers. They will be able to assess your heating system and provide an obligation free quotation.

Call: 020 8367 9969

Email: office@pettiferplumbing.co.uk