robert wrote in
:

On 05/03/2014 16:53, DerbyBorn wrote:
Roger Mills wrote in
:

On 05/03/2014 15:43, DerbyBorn wrote:
A friend is having trouble getting his downstairs radiators hot.
(Upstairs it balanced down to a minimum)
A plmber has replaced the pump to no avail. Today he did a power
flush but he connected to a radiator flow and return. I had assumed
that flushing was normally done at the pump connectors.

If there is a blockage then I believe the pipes under the floor are
the problem.

Sould he be trying to connect the power flush into one radiator -
and the return into a different radiator?

Chances are that any blockages are *inside* the radiators rather
than in the pipes. Best way of dealing with that is to take all the
rads off and take them outside and flush each one out with a
hosepipe.

Then flush the pipes (with the rads out) by opening one radiator
valve at a time until the water runs clear.

I am thinking that the lowest pipes are likely to be sludged. The
rads had new TRVs fitted a couple of years ago so some draining down
was done.

why the heck don't all plumbers fit and exterior drain point????

If Microbore (8/10mm) then blockage in the pipes is quite possible
especially if inhibitor wasnt added when the TRVs were installed.



It is 15mm