another of those days on a y plan

[buckley plumb]

called to a job today no htg or hw. find fuse in board blown and 13amp fuse in spur.trace to pump fault - replace pump with a rated all merchants now stock at £110 . all good but notice with programmer off the boiler and pump on running through bypass. remove htg on wire from junction box and its live find pump failing has welded contact in programmer closed . call sparky as I have busy day and call back later to see him . we replace programmer and still the same so I exchange for another programmer and now it works on htg but hw on wire is live with programmer off . we remove orange and white wires from junction box to zone valve and switch back on to find zone valve powers to htg position now we are puzzled.i get new Honeywell head and fit and now htg works fine and room stat but now hw on wire is constantly live . we put hw on zone valve stays in hw only , then I put htg on and zone valve moves to mid position then I turn cyl stat down and zone valve moves fully to htg only so its working as it should but turn htg and hw off and hw on wire is still live until hw is satisfied . sparky puzzled now and leave at that for now are there any sparkys that can shed some light this job has stressed me out.thanks ant

 

[SafeGasInstall]

Looks like to me that you are trying to install a Y plan into a w plan !?

 

[gassafe]

Might be easier to start from scratch

 

[Reg Man]

Agree with you there. Forget what's there, trace your wiring and go back to the original Y plan wiring diagram. I take it you have a ten way junction box. Tip I always use to cut down the confusion, all the green/yellows in one terminal, all the blues in another, that leaves you with only a few to think about.

 

[buckley plumb]

Agree with you there. Forget what's there, trace your wiring and go back to the original Y plan wiring diagram. I take it you have a ten way junction box. Tip I always use to cut down the confusion, all the green/yellows in one terminal, all the blues in another, that leaves you with only a few to think about.

that was my next plan to return with 10 way box and cyl stat - I just thought sparky would sort as I didn't have time to get involved but ended up having to

 

[mountainman]

Sparkies generally don't understand heating system wiring, especially 'Y' plan.

 

[buckley plumb]

Sparkies generally don't understand heating system wiring, especially 'Y' plan.

I have realised that now mate - been one of those wks it was a job I slotted in and wish I hadn't

 

[BLOD]

Is there a hw off wire from the programmer to the wiring ctr ?If there isn't it could have been wired up for hw to be permamently live to make the customer think htg works on its own.

 

[stevetheplumber]

i had one last week the pump was wired to the heating on the clock and there was no pump on hot water only boiler going to overheat cylinder stat fell to bit as soon as i touched it ,allegedly wired by BG

 

[lgastec]

Was it a Grudfoss UPS 2 you fitted by any chance? What make is the timer?