While you wait for answers, we may have found some information which could help you.
Click here for Boiler Heating LockoutPotterton Prima 60F- can you start it manually?
Potterton Perfoma 24. Hot water works fine No heating?
E133?
How to replace Potterton EP 3002 with EP 2?
Potterton ep22?
My potterton boiler keeps losing water pressure and condens?