Central Heating Header Tank Overflow - Expansion Pipe

[WSB]

Hi All,

Noticed that my central heating header tank over flow pipes was dripping water, so emptied a little water from it and adjusted the ball valve and all looked as though it was closing off fine.

However, since then I've noticed that the reason this head is overfilling is not due to the valve but due to the expansion pipe that empties into it.

We haven't had the heating on for ages but understand that if the boiler kettles, it will expand the into this header tank.

My thoughts are that I just need to turn down the boiler heater setting (Potterton Suprima) to stop it over heating the water.

Correct? or other things to consider?

Thanks

 

[denso13]

Correct?

Could be a blockage or restriction in the system causing pumping over into the F&E cistern.

 

[dilalio]

Likely blockage at the H section (where feed and vent) are connected. Many ways to sort this including new section which might be the easiest for a DIYer.

 

[WSB]

Thanks all. Tried turning down the boiler temp a bit in the case kettling was occurring but still getting the same issue.
Looking in the loft at the expansion pipe into the central heating header it disappears somewhere then somehow comes out in my airing cupboard in the room below.
Trying to track this expansion pipe from the boiler side, so I know which one it is.
Clues anyone? It clearly goes upwards but from where?

 

[WSB]

Where is the H section you mention? Thanks