Hi,
When the central heating is turned off there is a flow back up the vent pipe push hot water into the CH header tank. immediately followed by the sucking off air back down the vent pipe and into the system.
We live in a bungalow and there is less than 1.5 metres (about 4 foot 6 inches) of vent pipe between the main CH pipe where the vent pipe is connected to the header tank.
How do I stop this lost of water to the header tanks and the subsequent sucking of air into the CH system?
Thanks Pete