On Dec 30, 7:24*pm, "A Plumber" wrote:
"Vass" wrote in message

...







"Nick" *wrote in ...

Any suggestions for doing so please?
We will be replacing the aged back boiler in a couple of months.
The chap that will do the job has suggested that desludging prior would be
a
good idea. I fully agree but don't know how best to do so.
Conventional fully pumped system. Two motorised valves (CH & DHW), TRV's
fitted to all but one rad. Two zones. Will probably replace all TRV's in
the
process as they are donkeys years old.
System always has inhibitor, Fernox or Sentinel (can't remember), but
hasn't
been flushed for more than 20 years.
I could go for a professional powerflush as I can't do it myself. Too many
years & not enough diy time.
I can drain the system completely and add chemicals. Then drain again, add
more (other,if needed) chemicals and do this repeatedly.
Given that I have at least a couple of months, this seems a good option as
I
would prefer to do it myself if at all possible.
I realise that such drastic treatment will show up any potential
weaknesses
in the system (rusting rads etc), but now is the time for me to get it
done.
I hope this may not cause too many problems.
I have been told that hydrochloric acid might be a good starter and also
to
be careful with it. I have a fair quantity of HCL as we use it regularly.
I
would not know what rate to administer this at.
Alternatively Fernox DS-40 or similar.
Any thoughts or recommendations would be very much welcomed.
Time is not of the essence, but now is a good time to start.

Best wishes to all for a very happy and preposterous new year.

http://www.hss.com/g/51610/Central-Heating-Flusher.html
HTH

Power flushing will certainly find the weak spots in the system, if your on
meter they use a lot of water,personally if you've had fernox in
I would drain down, take each rad off (can inspect) in turn, flush with hose
pipe until water is clean,
refit and refill and run heating for w hile then drain down again. then fill
again with inhibitor when new boiler is fitted
I certainly wouldn't put hydrocloric acid in, don't think it would do the
system much good.- Hide quoted text -

- Show quoted text -

The above is right. Much better to drain down & remove the rads. Take
them outside & give a good blast with the hose pipe. If you can
remove the blanking plugs, so much the better. If they are more than
say twenty years old I would consider replacing them if money is not
an issue. Especially if there's been no inhibitor in the system. (It's
supposed to be changed/boosted regularly) When you remove them be
ready to catch the black gunge that runs out.
If there is huge quantities of gunge, I would replace all of them &
save future heartache. The black gunge being the remains of your
radiators.
I f possible give your system pipes a blastout with the hose pipe too.
I refuse to believe these chemicals do as good a job.