Plumbing Question

Is it worth power flushing an 11 year old worcester boiler plus 6 radiators?

My combi boiler has been clicking on and off rapidly and apparently the problem is the heat exchangers. The boiler is still working and effectively heating the radiators and water. I have been advised by one plumber that a power flush is needed, with an expensive quote. Another plumber has advised using Ferroquest instead. Many thanks, your advice would be appreciated.

8 Answers

Best Answer

£150 is a joke. It costs between £250 - £400 depending on the size of pipe work, amount of radiators, state and condition of tank in the loft and what lurks in the system! a lot of times, some radiators are so badly clogged that a power flush will not move the sludge. They have to be removed, cleaned out manually with a hose, replaced and then flushed. Also, the feed pipe work from loft tank may also be clogged or even blocked if a continuous amount of air is in the system and needs bleeding on a regular basis. A power flush will clear your heat exchanger, coils in the hot water cylinder, radiators and all pipe work.

Answered 23rd Feb 2011

Monray Domestic Services

Member since 6 Aug 2008

i agree with Monray Domestic Services good bit of knowledge there mate i do a powerflush everyday for a well known company they charge 275 plus vat for 5 hours if the system is really bad flush does not clear it manually gettin rads of is the only way and if you have 8 mm or 10mm it dosent work goes straight over the top of the sludge you get no flow back you need to take a rad off and check how much is there.

Answered 28th Feb 2011

R L Whitehouse

Member since 17 Nov 2008

No feedback

A power flush here in the SouthWest is usually <£400, some people do it for <£300, but you have to start wondering how thorough they are at this price. I would get it flushed and make sure your keep a record so that if the boiler does pack up in the next couple of years then it won't shouldn't need doing again when the boiler is changed. You would probably benefit from adding a Magnaclean at the same time as the flush, this should stop any bits that the flushing may miss from blocking the boilers heat exchanger again.

Or for less than £2000 you should be able to get a new boiler, a Magnaclean and a flush all at the same time.

Answered 21st Feb 2011

Blake Ecotec Ltd

Member since 8 Feb 2009

A power flush a good idea if your heating system is in a reasonable good condition. If your boiler is getting on it may pay to replace the boiler. When a new boiler is installed it should always be power flushed, if not your warranty will be invalid. A power flush will cost around £350 the chemicals will cost around £60-£80, then take in to consideration the machine and a days labour for 1 man and a labourer. If you are not paying somewhere around this you need to find out why because this is quite a standard price. A new boiler install should cost around £1650.
Hope this helps if you need any further information please give me a call.

Dave Giles

Answered 21st Feb 2011


Member since 17 Oct 2009

power flushing is definately worth doing. You shouldnt pay more than £150 really.

Answered 21st Feb 2011

NR Building Services

Member since 19 Nov 2009

powerflush uk will charge around £300 and travel up and down the country,if this is anything to go by

Answered 24th Feb 2011

Paul Caton Gas Services

Member since 23 Mar 2010

a powerflush would do the job and have a magnaclean fitted at the same time it would cost about £350 not £150 thats a joke.The only problem with a powerflush the chemicals will find any weak spot in your rads and they could start to leak especialy if they are old

Answered 21st Feb 2011


Member since 1 Jun 2008

Hi there,you could try doing a chemical flush,as long as you are able to follow instructions you can get the materials from any plumbers merchant[use the kind you put in with a mastic gun]its easier.then just put in inhibitor to protect it after flushing...Brian

Answered 21st Feb 2011

E&M Plumbing & Heating

Member since 26 Feb 2009

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