Radiators

I have a problem with two rads in my house... I have taken the rads off and flushed them out... drained gallons of water through the pipes/valves... I tried to balance the system.... started by turning off every other rad and left the two dodgy ones on... they seemed to heat alright... then slowly I opened the others in order to balance... I thought this was great... The following day when I turned on the heat these two rads failed to heat again...

Someone else suggested it could be water starvation... ie the pipes feeding these two rads are too small/smaller than the others.

I have had a few people look at it but it has baffled them all... I am about to call in a professional...

Just before you do- there could be a small leak somewhere in the system, thus when the system cools down air is drawn in to replace the lost water. The only way to be certain is to vent all the rads, tie up the ball cock feed to the expansion tank (the smaller tank) and turn on the boiler for 20 mins or so. If after the system cools down you notice a significant drop of water level in the expansion tank (allowing for the natural contraction of the water through cooling in the system pipework) this could be an indicator of a leak somewhere in the system. Examine all the rad valves, gland packing can fail. If in doubt get an installer to give an opinion.

Handy link lots of advice here


http://www.diynot.com/pages/pl/pl033.php


Good Luck