Grey wire.. Honeywell V4073A & Potterton EP2000 help

[gazzagee]

Moved into a new house and the heating is some what antiquated, I'm planning on changing the controller over to a Hive system but before I do I want to make sure its working correctly is the heating is.. pants and the kitchen Rad does not work but that another story.

The issue I have is the boiler seems to cut in and out all the time, and it looks like the system heats the HW when the CH is on regardless of the HW being on or off, now I'm thinking tell me if i'm wrong this is to do with the grey wire on the valve not being connected, so I connected it up, however this caused the heating to just be 'on' regardless if it was turned on or not, so I removed the grey wire again for now. I have removed the EP2000 from the all and looked at the wires to me it seems i'm missing the HW/CH off wires? or its just wired wrong, can some now cast their eyes over the photos and let me know.

 

[CountryFan]

You have a y-plan and do have a hot water off terminal on the Potterton, what you need to do is trace the wiring to the wiring center, as that just looks like they’ve used a choc block to join up. Grey should go to the cylinder thermostat satisfied

 

[gazzagee]

I've chased the wires back to the 'wiring center', (see attached) looks like the blue from the cylinder thermostat is connected to the grey wire

 

[CountryFan]

So your cylinder thermostat satisfied connection isn’t connected when it should be, also, the yellow in with the red doesn’t look the best connection.

 

[gazzagee]

I'm trying to work out what colour wire they are using for the satisfied connection, the room thermostat seems to be black which is connected to orange, the cylinder thermostat black also seems connected to orange and the blue is to the grey.

 

[gazzagee]

I think i'm going about this all wrong, please correct me if I'm wrong, but as i'm planning on changing the controller to a Hive system I can just rewire from the wiring center to the Hive box in the airing cupboard and remove the Potterton from the kitchen completely.
If so I can connect the correct wires including the grey one? and hopefully get the system working correctly.
Any help in wiring from this to the hive V3 heating & Hot water would be appreciated

 

[CountryFan]

Yes, but you’ll need to leave some of the original kitchen wiring, as that’s likely where the spur is located