At Dunnwell Plumbing & Heating we are members of the PowerFlush Association.  The PowerFlush Association was created to set a standard for power flushing companies in the UK and Ireland.  Our engineers are City & Guilds and NVQ Qualified plumbers.  As such we are qualified to carry out a power flush and re commission a heating system.


What is a Power Flush? - A powerflush is a cleansing process which aims to remove deposits of sludge, rust and any other debris from your central heating system.  These contaminants, if left, can seriously affect the efficiency of a heating system and in severe cases a powerflush is the only option available.


Signs that you might need a Power Flush - There are a number of signs to look for before deciding to go ahead with the powerflush process.  These include cold areas on radiators, excessive noise from the boiler or the heating system pump, discoloured water when you bleed the radiators and the slow warming of the heating system.  You might also notice the tap water getting cloudy, especially if there is a build-up of lime scale as well.


It is also recommended that the powerflush process is carried out if you intend to connect a new boiler replacement to an old heating system.  This is because most new boilers are condensing boilers and any contaminants already present in the heating system can quickly damage the internal pipe work of the new boiler.

Our City & Guilds and NVQ qualified engineers have been trained by Fernox (a world leader in the industry) in power flushing so you can be assured we have the right training and qualifications to carry a power flush and help restore your heating system.

Why Do I Need a Powerflush?


As sludge and/or debris build up in a radiator it affects the flow of water through it, eventually creating cold spots.  In the short term this will lead to decreased heating efficiency, higher energy bills and eventually a system breakdown which could even result in part of or all the system needing to be replaced including the boiler.


The picture to the left shows how sludge and debris settles to the bottom of the radiator which then creates cold spots.

It is not only radiators and boilers that are affected by sludge and debris.  As heating systems deteriorate the pipework that carries your hot water can become blocked too.  The can cause a reduced flow of hot water around your heating system.


The picture to the right shows how pipework can become blocked reducing hot water flow.

Can This Kind of Corrosion be Prevented?


Yes, when fitted, cleaned or on a regular basis heating systems should have a liquid called "inhibitor" added to them.  This slows down the rate at which the corrosion occurs minimizing the risk of breakdowns.  Inhibitor does not clean a system and is not a replacement for power flushing.


How Often Should I Have my System Powerflush or Add Inhibitor?


There is no set time frame for how often you should have a powerflush carried out or add inhibitor.  There are some basis checks you can carry out for yourself.  These checks are not fool proof but are a good indicator.  You can try one or more of the following;


• Bleed your radiator, the darker the water the more you need your system to be flushed.

• Check the condition of the water in your "Feed & Expansion Tank"; stir the water to disturb any sediment.  The darker the water the more you need your system to be flushed.

• Use a strong magnet and put it on your copper heating pipework.  Copper is not magnetic so if it sticks it is sticking to the build-up of magnetic sludge in your pipes.

How Long Will it Take?


Every heating system is different so the length of time a power flush will take will vary with each system.  As a general guide a power flush will take at least several hours to complete even on a small system.


How Much Will it Cost?


The cost will vary with each system but as a general guide we charge £60.00 per radiator.

A Word of Caution - there is no guarantee that a powerflush can fully restore your system and may cause leaks when rust, sludge and debris are removed from heavily deteriorated systems.

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Wakefield Office

25 Bradford Road, East Ardsley

Wakefield, WF3 2HE

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