Morning all - I replaced a trv in a large bungalow yesterday. To save draining down I bunged the header tank - rad working fine now but water not heating up. Assume there is now an air lock leading up to the coil in the tank ? How would I clear this ?
Hi. Try isolating rad circuit to get more action on the primary hot water circuit. Check for air release valves local to cylinder. Make sure ball valve is working in expansion cistern. Good Luck
Thanks justlead ; do you mean close down most of the rads and in doing so there should be more flow thro the coil? Also I noticed the ball valve in the header tank is well past it's sell by date - I mentioned to the owner I would replace but why would this cause an air lock?
Hi Yes close down the rad circuit or individual valves. When removing the bung from the cold feed to refill the bit you drained from the system can pull air if the ball valve is not replenishing the cistern.