suprima 80

sorry you must all be so bored of this question by now, usual flashing red light after 5-10 mins, however i notice that slight movement of ONE of the yellow thermistor wires just inside pcb connector can start it up (sometimes just getting flashing green with nothing else happening), or when its been running for a FEW minutes another slight movement will usually knock it off again but as i said only after its been running for a few minutes

i also noticed after the boiler had got up to quite a temp and still alight the boiler stat had no operation.

is this just classic pcb symptoms or possibly thermistor and/or leads

ive got all spare parts including PCB in the van so if this does need doing any tips or things to look out for as ive had a quick look at it and seems to be all new wiring looms and electrode leads

thanks

So why didn't you just try swapping over the pcbs ?

You're there at the job and you could have had an answer in 5 minutes

no i was there for a 'two minute' job to tighten leaken rad valve for the new tennants. only when i got there they mentioned the boiler. as i said having never done one, i didnt want to get bogged down, with other jobs to do

edit; sorry also to mention i never had thermistor and leads at the time

An old Suprima board can be full of bad connections. (So can a young one...).
A disconnected temp sensor though, makes the boiler come ON, it doesn't , as might be sensible, lock out if it sees the wrong value.