Plumbing Questions? Ask a Plumber for Answers ASAP
Probably , but can you tell me the pressure reading , please?
If the boiler resets then put on the heating , and see if the boiler attempts to ru n , can you hear the fan start , does the boiler try to ignite , is sparking ? Sorry but have early start . we can continue early morning , if you like
If you can see the ignition, then your issue will be either the flame recognition probe , or ( typical on these boilers ) the temperature thermistor , both reasonably cheap parts.
The thermistors can be checked with a multimeter on ohmsc.