It's the front white outer cover I am on about not the cover to the combustion element. With this cover off I can see the pump, combustion chamber, exhaust pipe? Etc.
Hi I have a valiant boiler with separate storage tank upstairs. Every few days the boiler spills out about a pint of water and then pressure drops so I have to top up water in the system and place a bucket underneath the boiler.
I als0 bleed the very top rad as full of air, but not always...