Non return valve on header tank cold feed

[patkelly67]

Hi, just a quick one (I hope).

Could a non return valve placed on the cold feed from the header tank cause pumping over from the vent pipe when the central heating circulating pump is on?

Thanks, Pat

 

[Dotty]

No...

It's dangerous. There shouldn't be an NRV on the cold feed.

 

[snowhead]

Sounds like it's pumping over and someone has fitted a NRV to try and stop it, quite why is a mystery.
As above get it removed then look at why it's pumping over.

 

[patkelly67]

Thanks. I'll remove it and see what happens.

 

[JeffD]

Hi, just a quick one (I hope).

Could a non return valve placed on the cold feed from the header tank cause pumping over from the vent pipe when the central heating circulating pump is on?

Thanks, Pat

if its pumping over I'd be looking elsewhere, ie circulation pump speed, system blockage somewhere

 

[patkelly67]

Removed NRV. It was an anti gravity valve on closer look, a fair size one as well! Anyway, pumping over has stopped (good news). Keeping an eye on the water level in the header tank as it may fill through cold feed outlet. Fingers crossed. Thanks for all the advice.