Motorised valve problem

[barrowfordred]

Hi there. I have a y-plan heating system and have replaced the mid position honeywell V4073 valve for a Horstmann (new from Screwfix). After swapping the wires over one at a time, like for like, the new valve doesn't power up. It always stays in the sprung position. I have checked the function of each wire and all is correct. I have a temp stat on the water cylinder and a room stat.
Putting the old valve back on doesn't make any difference, this one doesn't work either, although it used to. I changed it beacause the spindle was sticking.
Seems to point to a faulty valve(s)!!!!!
Anything obvious I've missed.

 

[kevplumb]

is the valve getting power ??

 

[barrowfordred]

The blue neutral is powered, the input from the room thermostat (white) has power when the stat is turned up. All the other wires (Grey water staisfied, Orange output to boiler) seem to be fuctioning as they should.
How can I wire the valve so that it is forced to motor open to check it?

 

[bripl]

if you have power on the neutral you have a fault check your neutrals are connected correctly

 

[doitall]

Blue wire should be connected to neutral.

When heating only is selected live on Grey, Orange and White valve should open to port A.

Hot water only live on Orange wire only

Hot waterand Heating live on White and orange wire valve in mid position.

Terminal 2 on room stat must be connected to neutral

Thanks to Alan E [/b]

 

[barrowfordred]

Ok here's what's happening.
Heating only - White & Grey live, Orange NOT! (Orange won't energise 'till the motor has turned to operate the micro switch)

Water only - White live, Orange live, Grey not.

water & heating - White live, Orange live, Grey not.

By the way - moving the lever to manual operates the valve but it then returns to the sprung position. It will not energise.

 

[doitall]

the Grey should be connected to 2 on the cylinder stat

Orange to terminal 1 on the cyl stat

room stat.
2 neutral
1 programmer htg on
3 white

 

[barrowfordred]

Orange & Grey are connected as you say.
The room stat only has 2 wires (plus earth).
Red input and a black output.
The Black output is connected to white on the valve.
I am sure the wiring is OK .
The valve will not move to energise Orange to bring the heating mode on.
I have re-wired the old motor body as it was before I started and it STILL doesn't work. I know this seems as though the wiring has been changed, but I don't think it has.
Moving the lever to manual and jamming it there starts the heating. This will switch on and off with the room thermostat, so I leaving it like this for now 'till I can find a solution. This of course means no hot water mode.

 

[doitall]

It cant be wired right or the grey would be live.

Visit the Honeywell site and download the yplan drawing,

http://content.honeywell.com/uk/homes/systems.htm#Y Plan

and let us know how you get on, bet its something simple

 

[barrowfordred]

It will be something simple.
The wiring is as the honeywell diagram , and all the other diagrams I've printed off the 'net.

 

[doitall]

with the power off remove the wire from terminal 3 in the room stat.

Turn the power back on, programmer calling for htg only is terminal 1 live, turn stat up is terminal 3 live

 

[ChrisR]

'Old on chaps, not all room and cylinder stats have the same terminal numbers!
Use the Honeywell diagram and check if your stats match theirs

 

[doitall]

very true Chris, however there should be a live across the room stat which powers the white.

The grey is switched between HW on and HW off in the time controller and should be live when the cylinder stat is not calling for heat.

The motor requires a neutral this need to be checked

 

[ChrisR]

Did I say that was wrong?!

 

[doitall]

Did I say that was wrong?!

Did I say you did

any suggestion may be helpfull m8