honeywell st699 problem

[vipey]

Hi my friend today changed his programmer for his boiler as it kept on tripping the fuse and not turning on it was also burnt on back and smelt so wasn't good .so swapped it like for like for another Honeywell st699b programmer after doing this his boiler will not fire up he says the pump is coming on and also the divertor valve sounds like its moving could he be missing somethink here ? its a regular glow worm boiler don't no model , could he have burnt the pcb out somehow ? , he surely couldn't have wired it wrong as he didn't even have to touch the wireing as was on a plate . any ideas would be greatfull

 

[jase158]

did he check the wiring?

 

[mountainman]

Straight swap the ST699, as long as your friend didn't change the backplate then nothing can go wrong.

 

[jase158]

not always but sounds like loose wire or boiler has gone

 

[vipey]

yes its very weird , straight swap left back plate on so didn't need to touch anythink wire wise , he checked wiring was correct and so did I when at home , he took the face off the other wireing interlock where they all meet and said only think that didn't make sence was a blue and yellow wire that wasn't connected to anywhere but no one has touched them but couldn't work out if they went anywhere hope makes sence lol , he said when he 1st turned boiler on he thinks it might have fired up then shut down althou there is a flame there all the time ,

 

[mountainman]

You need the services of an electrically competent GSR imho.
Probably a straightforward fix though.

 

[vipey]

yea that's what he doing just thought id ask

 

[Mucckker]

Will A new ST699 will work and fit old style ST699B brown one ?

 

[Mucckker]

Will the new white ST699 fit the old style brown ST699B base plate without altering the wiring

 

[gassafe]

Is it set up for fully pumped & not gravity? I'm not sure if the honeywells have this link