I have changed a rad in bathroom and slightly altered the pipework, to do this I drained the system by tieing the ball cock in the expansion tank and attached a hose to to lowest bleed point and removed all the water from this point.
Upon refill i believe i have an airlock in the pipwork. Upstairs rads get hot including the new one but 2 of the 3 downstairs dont get hot not even the approach pipes are hot. The 2 cold rads each have a drain valve on and when i attach the hose to these 1 releases cold water which gradually turn to hot and the other doesnt release anything. The onw that releases water has the drain valve on the return and the one that releases nothing has the drain valve on the inlet.
Please can some one help.
Upon refill i believe i have an airlock in the pipwork. Upstairs rads get hot including the new one but 2 of the 3 downstairs dont get hot not even the approach pipes are hot. The 2 cold rads each have a drain valve on and when i attach the hose to these 1 releases cold water which gradually turn to hot and the other doesnt release anything. The onw that releases water has the drain valve on the return and the one that releases nothing has the drain valve on the inlet.
Please can some one help.