I've just had a new central heating pump put in as the old one was
leaking to earth and tripping the rcd switch.

The plumber said there was probably a lot of sludge in the system and
this could have damaged the old pump, and I should think about having a
power flush. However, when he drained the system, the water coming out
of the hose looked clear, and a quick google on this group suggests that
a power flush isn't necessarily worth doing.

Is it worth my taking a radiator off and flushing it myself to check for
sludge? Or is the clear water (although I only checked it once during
the process) from the draining down sufficient proof that it doesn't
need doing? Any other suggestions I haven't thought of are very welcome
- this is a long way from being my area of expertise.

- guy

Guy Snape wrote:
I've just had a new central heating pump put in as the old one was
leaking to earth and tripping the rcd switch.

The plumber said there was probably a lot of sludge in the system and
this could have damaged the old pump, and I should think about having
a power flush. However, when he drained the system, the water coming
out of the hose looked clear, and a quick google on this group
suggests that a power flush isn't necessarily worth doing.

Is it worth my taking a radiator off and flushing it myself to check
for sludge? Or is the clear water (although I only checked it once
during the process) from the draining down sufficient proof that it
doesn't need doing? Any other suggestions I haven't thought of are
very welcome - this is a long way from being my area of expertise.

- guy

If the rads are noticably cold at the bottom when the heatings on high, then
they may need flushing.

I did two in a couple of hours yesterday, simply turned of the flow at each
end, uncoupled and with the help of a friend, carried into the back yard for
a serious blast out with the hosepipe - the sludge was the blackest of
black, and my jeans, despite three washes, are still stained.
One of the rads was particularly bad, and judging from the sludge on the
patio, there must have been at least a few kilos of the stuff in it - only
the top 2 inches ever got hot, and this is a 6 foot long radiator!!

If the rads are noticably cold at the bottom when the heatings on high,
then they may need flushing.

I did two in a couple of hours yesterday, simply turned of the flow at
each end, uncoupled and with the help of a friend, carried into the back
yard for a serious blast out with the hosepipe - the sludge was the
blackest of black, and my jeans, despite three washes, are still stained.
One of the rads was particularly bad, and judging from the sludge on the
patio, there must have been at least a few kilos of the stuff in it - only
the top 2 inches ever got hot, and this is a 6 foot long radiator!!


Presumably some parts of the pipe runs are even lower than the bottom of the
radiators. Whilst the flow through a pipe may have a purging effect, you
will also have sludge settling in the pipes.

On Tue, 15 Jan 2008 09:28:05 +0000, John wrote:


If the rads are noticably cold at the bottom when the heatings on high,
then they may need flushing.

I did two in a couple of hours yesterday, simply turned of the flow at
each end, uncoupled and with the help of a friend, carried into the
back yard for a serious blast out with the hosepipe - the sludge was
the blackest of black, and my jeans, despite three washes, are still
stained. One of the rads was particularly bad, and judging from the
sludge on the patio, there must have been at least a few kilos of the
stuff in it - only the top 2 inches ever got hot, and this is a 6 foot
long radiator!!


Presumably some parts of the pipe runs are even lower than the bottom of
the radiators. Whilst the flow through a pipe may have a purging effect,
you will also have sludge settling in the pipes.

That's when things start to go really wrong.


--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html

Ed Sirett wrote:
On Tue, 15 Jan 2008 09:28:05 +0000, John wrote:


If the rads are noticably cold at the bottom when the heatings on
high, then they may need flushing.

I did two in a couple of hours yesterday, simply turned of the flow
at each end, uncoupled and with the help of a friend, carried into
the back yard for a serious blast out with the hosepipe - the
sludge was the blackest of black, and my jeans, despite three
washes, are still stained. One of the rads was particularly bad,
and judging from the sludge on the patio, there must have been at
least a few kilos of the stuff in it - only the top 2 inches ever
got hot, and this is a 6 foot long radiator!!


Presumably some parts of the pipe runs are even lower than the
bottom of the radiators. Whilst the flow through a pipe may have a
purging effect, you will also have sludge settling in the pipes.

That's when things start to go really wrong.

The ones I flushed seem to be working perfectly, although I agree that, as
my pipes are lower than the rads, these too must be full of ****.
I still have one radiator downstairs to do (upstairs ones are fine), but
surely, emptying the downstairs ones, must in some way help towards clearing
the sludge in the pipes?

"Phil L" wrote in message
.uk...
Ed Sirett wrote:
On Tue, 15 Jan 2008 09:28:05 +0000, John wrote:


If the rads are noticably cold at the bottom when the heatings on
high, then they may need flushing.

I did two in a couple of hours yesterday, simply turned of the flow
at each end, uncoupled and with the help of a friend, carried into
the back yard for a serious blast out with the hosepipe - the
sludge was the blackest of black, and my jeans, despite three
washes, are still stained. One of the rads was particularly bad,
and judging from the sludge on the patio, there must have been at
least a few kilos of the stuff in it - only the top 2 inches ever
got hot, and this is a 6 foot long radiator!!


Presumably some parts of the pipe runs are even lower than the
bottom of the radiators. Whilst the flow through a pipe may have a
purging effect, you will also have sludge settling in the pipes.

That's when things start to go really wrong.

The ones I flushed seem to be working perfectly, although I agree that, as
my pipes are lower than the rads, these too must be full of ****.
I still have one radiator downstairs to do (upstairs ones are fine), but
surely, emptying the downstairs ones, must in some way help towards
clearing the sludge in the pipes?

I have never had a great deal of sludge when I have removed radiators for
decorating - any sludge removed must help - I wish systems always had a
sludge trap that was easily serviceable.

There must be a heck of a lot for it to effect the radiators.