i added a towel rad in the toilet on the downstairs circuit, but i cannot seem to get all the rads downstairs warm together, i can close off any two of the five rads downstairs and get the other three pumping hot but not all together. it is a sealed system which i can get the pressure upto 2.5 bar if required, when i bleed the rads that have no heat ther is no air just water. i note there is a bleed valve above the pump should i bleed from this point. any ideas please ?

hopeful Alan, February 2008

Just TRY balancing. The water will take the easiest route back to the boiler.
If you have 2 rads that wont heat up, turn off the other 3 valves (1 side only!) then open them 1/4 turn.
Start up the boiler & see if that helps them ALL warm up. If it does, fine tune this 'balancing' to get supply to every rad more even.
Hope this is your problem solved.

Steve, February 2008