cb24/28 alpha boiler

[alancook766]

recently replaced valve on filling loop on my alpha boiler refilled and fired up.
now pressure keeps increasing when heating up. able to control by turning stat down on ch, eventually pressure drops too low and i have to reset.please help

 

[45yearsagasman]

You need to check the expansion vessel is charged and the diaphragn is intact. See FAQ's where is a good section on exp vessels.

 

[alancook766]

thankyou for your reply the boiler has no expansion vessel.
do you think the automatic air vent is not working causing the air to expand

 

[Gasop]

thankyou for your reply the boiler has no expansion vessel.
do you think the automatic air vent is not working causing the air to expand

With the control panel lowered you can see the bottom inch or so
of the vessel. It's the red bit you can see at the very back.

The charging valve is at the very top of the boiler.

 

[45yearsagasman]

The boiler has no expansion vessel!!!!!! Well in that case I won't bother to advise you anymore.