Combi Boiler Expansion Vessel

[dave12]

Hi,

Could someone please clarify something for me?

I have a combi boiler that when it is cold the nominal pressure is around 0.5bar. Once the heating is on and up to temp, the pressure sits at around 1.5bar. This makes sense to me as there is expansion taking place in the system, hence the increase in pressure. Is this normal?

My wife has now told me (I am away) that when the heatin is on there is water passing through the over flow outside. The pressure of the system is now 3bar. She has been advised that the Expansion Vessel needs replaced. Does this sound correct?

It sounds to me that the system has been topped up too much when cold. So when the heating goes on, the pressure rises further, exceeding 3bar and so the relief valve activates and releases water through the over flow.

Any opinions are much appreciated. Many Thanks

 

[Agile]

You would not need to search much on this site to read all about your problem and then you would not have to do your own ( wrong ) guessing.

Either the vessel is failed or it may just need recharging.

You glibly say "She has been advised " without indicating exactly who said that and if it was after inspecting the boiler.

Tony

 

[Mcfly1]

swap the tony for ****

 

[Soggy_weetabix]

swap the tony for ****

Get lost and give advice.

Recharge the vessel or replace it.

Dave