Rising pressure on Potterton 24E system bolier

[vicar227]

Hi ,
I have a Potterton system boiler 24E. The pressure keeps rising steadily when the unit is firing, it then releases the pressure through the pressure relief valve at 3bar, unfortunatley when i turn the unit off the pressure still rises overnight and vents as welll!! Any suggestions as to whats wrong? Its a mains fed system, gas boiler .
Ta
V

 

[ArtfulBodger]

Check the filling loop taps are not slightly open. Disconnect the filling loop if possible.

As it's doing it when the system isn't running it is unlikely to be your expansion vessel and most likely to be the aforementioned filling loop.

 

[vicar227]

Hi,
checked filling loop and its defo shut and tight, anything else that it might be??

 

[ArtfulBodger]

On a sealed system boiler there is only one way water can be entering the system and causing the pressure to rise, even if the boiler is off. That has to be the filling loop.

Why not disconnect it and see if that makes any difference?

 

[Agile]

If you want us to help you then you have to follow our instructions and remove the filling loop in accordance with the water regulations.

I assume you are not a real vicar?

Tony

 

[meldrew's_mate]

Father (well, you could be ),

Do you have a mains pressurised hot water cylinder (Megaflow, etc). If so it's possible the heater coil inside has pinholed, though very unlikely as the mains pressure reducing valve would also have had to fail allowing cylinder pressure to rise above 3 bar.

It's almost certain to be the filling loop as mentioned above, do as the boys say and remove it to be sure.