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What is a power flush and why do I need it?

As your boiler and central heating system ages, it is often unavoidable that rust and other substances will form within your boiler, pipework and radiators. Substances such as rust and other deposits, are commonly referred to as ‘sludge’ by professional engineers.

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What is a power flush and why do I need it?

A power flush is known as a cleansing process which removes sludge that has built up inside your central heating system. If these substances are left in your system, it could have an impact on the efficiency of your heating system by preventing even distribution of heat around your home.

A power flush could be an ideal solution to clean and maintain your central heating system to improve the amount of heat permitted from your radiators. Eventually, the sludge in your system could also cause severe blockages and damage, leading to a costly breakdown to repair. During a power flush, water is sent rapidly through the system to extract debris, limescale and sludge.

When do I need a power flush?

There are a number of symptoms to look out for which could suggest that you have sludge or corrosion in your system.

As part of an annual service, a Gas Safe engineer will perform various tests and visual checks on the boiler and heating system; during which the engineer may be able to identify potential areas of corrosion or sludge build-up. The engineer will advise if a power flush is required, and make you aware of any potential leak risks which may arise in the most corroded areas.

If you service your boiler annually then a preventative power flush every 5-6 years could be all that’s necessary to clear debris and prevent any substantial blockages occurring. However, the likelihood of rust and sludge forming often has a lot to do with the materials used on your heat exchanger. For example, copper heat exchangers are more durable than stainless steel which will corrode at a quicker rate.

We usually recommend having a power flush before a new boiler installation. This is to prevent any pre-existing rust and sludge in your pipework or radiators causing damage to your new boiler.

How much does a power flush cost?

The price of a power flush depends on the size of your heating system and the complexity of the work involved, but generally prices start at around £300. Although this may seem an expensive service, there are many benefits to a power flush which could help you save money over time.

What are the advantages of a power flush?

Here are some of the ways in which your central heating system could benefit from a power flush:

Can I perform a power flush myself?

We do not recommend attempting to perform a power flush yourself. Carrying out a power flush is a complex and risky process with specialist chemicals and equipment to be handled. To ensure the power flush is performed correctly and safely, ensure you book a fully qualified and Gas Safe registered engineer.

If you have noticed any of the symptoms mentioned in this article, we recommend seeking professional advice on the best solution as soon as possible. To book a power flush with one of our expert Gas Safe engineers, give our team a call on 0203 805 4581 .

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