3 way valve wiring

[nicol]

Hi, could anyone please tell me how to wire in a new 3 way valve? The problem i have is that the new one (Horstmann Zoneplus Z322) has orange, blue, grey and white wires, the old one has green, brown, white, blue and black wires. Is there any way i can find out where the new wires go?
Thank you, Nic

 

[ollski]

Not without knowing what the old valve was

 

[nicol]

Had a look it says Tower Heating Components model T679BR340 30L0. Probably means nothing now as it was fitting over 25 years ago, but did find a small wiring diagram on it says Brown - MID posn Brown/White - DHW Brown/Black - HTG. Does that help at all? Thank you.

 

[scatmanjohn]

Had a look it says Tower Heating Components model T679BR340 30L0. Probably means nothing now as it was fitting over 25 years ago, but did find a small wiring diagram on it says Brown - MID posn Brown/White - DHW Brown/Black - HTG. Does that help at all? Thank you.

OH NO...i have only ever seen one of them things, If you take the top cover off has it got a weird looking synchron motor(looks like one sat on top another)?

I ended up pulling all the wires out of the wiring centre and starting again.

 

[nicol]

I didnt look inside, seems its not an easy job then?

 

[scatmanjohn]

I didnt look inside, seems its not an easy job then?

Afraid not..its not a simple wire for wire swap if its the one i'm thinking off.

One of the old timers on here might have a better idea.

 

[nicol]

Ok, thank you anyway.

 

[nicol]

4 wires cant be this hard surely?

 

[MANDATE]

The modern 3 port mid position valve with the colours white, grey, orange, blue and green. are wired as follows.
green is earth. blue is neutral.
programmer supplies room stat and switched live from room stat leads to the 'white' on valve. This gets the valve to mid point.
When HW is satisfied or not switched on then the grey is made live, this comes from two sources. The satisfied terminal of the cylinder stat and also the HW OFF terminal of the programmer. If the grey is made live it takes over from the white at mid point and drives valve to CH only position.
When this occurs it triggers a microswitch and makes the orange live and this is used to fire the boiler, because the primary method of firing the boiler through the cylinder stat is no longer there.

 

[ollski]

Is the tower valve the one with the red actuator?

 

[scatmanjohn]

Is the tower valve the one with the red actuator?

I don't think so.

The one that i am talking about looked similar to a honeywell but nearly twice as tall.

 

[corgiman]

the old tower heads use to be red

like scat says they are just a HW rip off now

 

[nicol]

The modern 3 port mid position valve with the colours white, grey, orange, blue and green. are wired as follows.
green is earth. blue is neutral.
programmer supplies room stat and switched live from room stat leads to the 'white' on valve. This gets the valve to mid point.
When HW is satisfied or not switched on then the grey is made live, this comes from two sources. The satisfied terminal of the cylinder stat and also the HW OFF terminal of the programmer. If the grey is made live it takes over from the white at mid point and drives valve to CH only position.
When this occurs it triggers a microswitch and makes the orange live and this is used to fire the boiler, because the primary method of firing the boiler through the cylinder stat is no longer there.

Thank you very much for that, do you have any idea how they swap with the brown, white, blue and black wires of the old valve?

 

[nicol]

Is the tower valve the one with the red actuator?

Looks like a little tin box to me.

 

[MANDATE]

I don't know how they swap, but I think it should be easy to test them.
With HW off and CH off only one of your wires should be live, that should go to grey. (comes from the programmer HW OFF)

With HW off and CH on another wire should become live/dead as you turn room stat up/down, that one should go to the white.

With HW on and CH off white will be dead/ grey will be live, but another wire will become live, this is because power is going from cylinder stat to fire the boiler. Now it will become dead if you turn stat down or HW off and this wire goes to the orange(so boiler can fire up on CH only)

The wire that never becomes live will be the neutral.
I would expect the neutral to be either the black or blue.