prob with worcester 24i

[fergie]

hi all,
got a prob with a worcester 24i, on demand the boiler fires for about 15 secs, then shuts down, its not the pump( exchanger overheat), i have a feeling its something to do with the flame recognition system as the boiler continue's to spark after the burner has lit and then shuts down?
anyone had any simalar problems with worcesters?

p.s yes in i am registered, (i know how annoying it is when jo bloggs start s asking technical questions!!)

fergie

 

[ChrisR]

First thing to enter my head - check the flame recognition electrode /wire/connection to the pcb. Flame in contact with said electrode?
Got a sensitive enough meter to measure the current? (careful or you'll zap your meter!)

 

[COG]

If you want to check the flame senser look for betweem 4- 6micro volts but its easier to just replace it than check it. Crossed polarity will allso gave the same fault so check if any wireing has been done then check boiler, but its usually the flame senser. ps i assume your min gas pressure is ok (around 0.5mb at least )