by DONFRAMAC »
Tue Nov 20, 2007 12:39 am
Try balancing the rads. by first almost closing-off the manual isolator valves to the upstairs rads, so that a setting of 4 on their thermostatic valves still give enough heat;---- then you should get flow downstairs, where you should also balance the rad inputs. Check the needle inside the thermostatic valve on the cold rad. is free to move by removing the head and pushing the pin in and out. Sometimes it gets stuck with hard deposits, which can respond to a careful tap with a small hammer.
Some people resort to removing the rad. to outside, and flushing it with the garden hose.
Personally, I just dumped the rad. and fitted new valves, after running a lot of water thro' the pipes and recharged the system using fresh anti-corrosion inhibitor.
( Obviously your rads. that have just manual valves need to be closed-off while you are trying to encourage flow to return to your problem rad.)