As part of a revamp to the downstairs cloakroom I re-routed the
radiator pipes up and over the doorway (meant I had a clean wall for
the shower cubicle). So they now do an inverted "U". Since doing
that the radiator has not got warm when the system is on, all others
are OK. They have been bled (many times and the valves are open). If
I remove a bleed screw, eventually warm water will come out - so the
feed is OK. I have fitted an automatic bleed as high as I can up the
wall on the return pipe, that has had no effect.
Do I just accept that the additional pipe run up and over the room
(approximately 9m out [3m up, 3m across and 3m down] out and back) is
now just too much for my pump and simply fit a more powerful central
Anything else I can try first?
Sounds like you need to rebalance the system or just perhaps some crud
has been dislodged and blocked a pipe.
I don't like the sound of "eventually warm water will come out"
Does it still only creep out when the pump is off?
Shut the other valves off and force so flow through the errant radiator.
Thanks for the reply. Poor choice of words! It comes out after being
cold for a while - it is furtherest from the heat source. Pressure is
good. I have tried turning all the others off, but with no luck - it
Turn off all the other rads and run the system for a while. Hopefully
this will push the airlock through to the cold rad. You should hear
gurgling in the cold rad. Keep checking for air in that rad. If
successful, turn all the others back on and all should be well.
If that fails, there are other methods to try, but are a bit more drastic.
It is almost certainly an airlock. Once cleared, the pump should easily
cope with it.
The guaranteed method to clear the airlock would be to connect a
hosepipe from the water mains and blow the airlock back through the
system from the offending rad, but it's not easy to do and would need
two people. One to turn the hose on and off when necessary and the other
on the rad. Best left to a plumber though. Not recommended on a combi
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