Today had to fit new valves on radiators of a vented system. Drained system, pain as there wasn't a low level drain off valve. Fitted new valves, including a drain off. When I went to turn on the water at the F&E tank I noticed it still had water above the outlet pipe. Thought 'this could be trouble', F&E tank filled but system didn't. Thought that the outlet pipe was blocked, it goes straight down to the air separator but has 2 x 90 bends before it enters it.
First tried shoving a piece of wire down it, no difference. then tried filling from mains through new drain off, partially filled system hoping it would blow through outlet pipe to clear blockage, however only came out through vent pipe in to F&E tank. Vent pipe goes straight up from air separator to above F&E tank. Below air separator is pump and 3 way valve, and next to them hot water tank. Opened bleed valve on pump, dry. Above top feed to hot water tank is a bleed screw, dry. Lashed up a pipe from inlet mains with a hose and tried forcing mains water down the outlet pipe, it did not appear to make any difference.
I am fairly confident it is the outlet pipe from the F&E tank that has a blockage, probably at the 90 deg bends. It is an old system that has not had anything done to it for quite a while, hard water as well. Going back tomorrow to remove outlet pipe and check for blockages, is there anything else I can check.
Thanks for any relies.
First tried shoving a piece of wire down it, no difference. then tried filling from mains through new drain off, partially filled system hoping it would blow through outlet pipe to clear blockage, however only came out through vent pipe in to F&E tank. Vent pipe goes straight up from air separator to above F&E tank. Below air separator is pump and 3 way valve, and next to them hot water tank. Opened bleed valve on pump, dry. Above top feed to hot water tank is a bleed screw, dry. Lashed up a pipe from inlet mains with a hose and tried forcing mains water down the outlet pipe, it did not appear to make any difference.
I am fairly confident it is the outlet pipe from the F&E tank that has a blockage, probably at the 90 deg bends. It is an old system that has not had anything done to it for quite a while, hard water as well. Going back tomorrow to remove outlet pipe and check for blockages, is there anything else I can check.
Thanks for any relies.