While you wait for answers, we may have found some information which could help you.
Click here for Central Heating Loud Noise Boiler
how can i fix my sabre he 2.5, green light flickers on and off not staying ?
Sabre he will not work with combustion cover on?
Sabre 29he plus combi condensing Boiler?
How to fix my Sabre 24 passing water to the overflow?
Sabre boiler keeps switching off?
Why does my Sabre 25HE pcb fuse keeps blowing?