While you wait for answers, we may have found some information which could help you.
Success
Message
Big bang on ignition?
optima 701 pressure rises when heatings on drops when off?
Why does the Hawk II Optima keep turning on central heating without request?
how do i depressurise a ferrolli optima boiler?
Why do my TRV's rattle?
how can i fix boiler?
high pressure when heatings on?
Optima failing to fire up?
Trianco Optima Boiler Programmer Fault (QA73)?
how can i fix my ferolli optima 701?
OPTIMA 701 Ferrori heating problem?
Pilot light will not ignite?