y plan valve

[priceyson]

hi i have a y plan valve that works fine on ch hw but when on ch only its putting 240volts onto the hw opening up the valve for both , the pump and y plan was changed recently, the ch was comin on with hw replaced timer and that stopped that, the boiler doesnt fire up on hw when ch roomstat is turned down but still puts 240 onto the valve???any ideas

 

[seco services]

hi i have a y plan valve that works fine on ch hw but when on ch only its putting 240volts onto the hw opening up the valve for both ,

wouldn't say it puts 240v onto the valve as the hw don't have nothing to do with the valve as such.

more like the grey wire is not becoming live when only ch on.
sounds like a complete wiring c*ck up

where is it putting live onto the valve as you say what colour wire ?

 

[priceyson]

when in ch mode there should be 240 on white wire and in hw 240 on orange wire to y plan

when on hw only theres 240 to orange wire turn down cylinder stat the voltage goes and theres nothin on the white wire

when in ch mode theres 240 on both orange and white wire turn down room stat 240 goes but turn down cylinder stat and the 240 remainsmon orange wire

before timer replaced there was 240 on orange wire when ch was on , replaced timer and that solved that problem!!

there shouldnt be 240 at orange wire when ch only on should there?

 

[matt1e]

hi i have a y plan valve that works fine on ch hw but when on ch only its putting 240volts onto the hw opening up the valve for both , the pump and y plan was changed recently, the ch was comin on with hw replaced timer and that stopped that, the boiler doesnt fire up on hw when ch roomstat is turned down but still puts 240 onto the valve???any ideas

yes its wired wrong or the replacement programmer is

the valve will always have 240v on it unless power is off at the spur

ch off hw off....240 on grey
ch on hw off ...240 on grey(permenant)and white and orange(depending on demand)
ch off hw on.....240 on grey or orange depending on demand
ch on hw on....240 or 115ish on gray depending on demand/position of valve and 240 on white and orange depending on demand
to add to this there will also sometimes when white grey or orange will be at 0v (depending on demand) but as I said earlier there will never be a time when there is not 240 on at least one colour (unless the system is turned off at the spur),

Matt

 

[seco services]

when in ch mode there should be 240 on white wire

thats ok.

and in hw 240 on orange wire to y plan

240v isn't coming from the valve it is coming from the cyl stat which is in the same terminal as the orange.

when on hw only theres 240 to orange wire

240v to orange terminal live is from the cyl stat.

turn down cylinder stat the voltage goes and theres nothin on the white wire

is this with only hw on.

when in ch mode theres 240 on both orange and white wire

thats ok

turn down room stat 240 goes

ok

but turn down cylinder stat and the 240 remainsmon orange wire

only if heating still calling.

before timer replaced there was 240 on orange wire when ch was on , replaced timer and that solved that problem!!

heating on should be 240v on white/orange.

there shouldnt be 240 at orange wire when ch only on should there?

yes

 

[matt1e]

there shouldnt be 240 at orange wire when ch only on should there?

yes thats what fires the boiler

 

[matt1e]

seco you are too quick for me

 

[seco services]

i had to read it 6 times.

 

[matt1e]

when on hw only theres 240 to orange wire turn down cylinder stat the voltage goes and theres nothin on the white wire

But is there on the grey when you turn it down?

 

[D_Hailsham]

Read FAQ 17 - How the Mid-position Valve Works. It has full fault finding info.

 

[Paul Barker]

So at the moment you've got two combis in a commercial building on Y plan, and you want to know if a domestic gas fitter can sort them out but while you are wating you thought you'd have a go anyway?

Or are you not Gas Safe registered doing illegal gas work?