Worcester boiler pressure rising

[JimPickens]

The pressure on my boiler seems to rise when I turn the heating on in 10minutes it went up 0.5 and in 30 it was at the 3 red mark, theres also a clanging noise the boiler makes which sounds like it goes off and on again?

all my radiators work but theres an issue with 1 which I can't bleed because the valve has rounded up so the key doesnt work anymore

also should the filling loop key be left in the boiler? if so on the locked or unlocked padlock?

 

[GavThePlumber]

No take the key out, turn it so the arrow on the key points to the open padlock position and pull the key down and out, clip it back into the tray when done.

What is the pressure in the boiler when cold?

 

[twgas]

You need to check the expansion vessel, sounds to me as though it needs recharging. The key should be removed once the pressure is correct.

 

[JimPickens]

No take the key out, turn it so the arrow on the key points to the open padlock position and pull the key down and out, clip it back into the tray when done.

What is the pressure in the boiler when cold?

It's around 1.5 previous owner always had it in the boiler i've recently started taking it out and this happened =/

 

[GavThePlumber]

Coincidental, as twgas as said, you need to check the EV, press in the schrader valve, if water comes out of it you will need to replace it.

 

[JimPickens]

Alright tyvm both