I am about to change out my boiler for a Kelson c 40 and have had a
number of firms round
quoting between £4500 and £6000 to replace my floor standing boiler.
Our existing heating system is made up of a number of old cast iron
rads fed by a single pipework which I believe to be mild steel and was
installed about 1920s.

I have spoken to Kelson and they recommend power flushing prior to the
installation of their product. However most of the plumber do not seem
to agree, prefering to use chemicals to rinse out the system.

Also the use of a filter on the return - will this cause problems with
the flow pressure, given the system I have.

On Tue, 26 Sep 2006 12:48:59 -0700, SMPW wrote:

I am about to change out my boiler for a Kelson c 40 and have had a
number of firms round
quoting between £4500 and £6000 to replace my floor standing boiler.
Our existing heating system is made up of a number of old cast iron
rads fed by a single pipework which I believe to be mild steel and was
installed about 1920s.

I have spoken to Kelson and they recommend power flushing prior to the
installation of their product. However most of the plumber do not seem
to agree, prefering to use chemicals to rinse out the system.

Also the use of a filter on the return - will this cause problems with
the flow pressure, given the system I have.

What is clear is that the system should be clean before you put the new
boiler on. To certain extent this will depend on the state of the existing
system. Neither I nor Keston have seen this.

Whilst the age and materials used bode well for the existing system been
clean the bore of the pipes is likely to ease things.

Given that you may be adding extra pipe work to go to a modern
fully pumped twin pipe system, I would give consideration to removing the
iron pipes. If this is not practical then there are still other lines of
attack.

1) Firstly the system can be got clean by chemicals and/or power flushing.
2) You could go for a plate heat exchanger by the boiler, have a clean new
primary for the new boiler and keep the old system intact.


--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
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