Strange programmer wallplate wiring - no HW

[Mattt]

Hello,

Hopefully someone might be able to assist me!

I've been playing around with my new Tado (smart thermostat) system and have noticed something odd that the HW turns the CH on but doesn't heat any water.


I recently moved into the house and the previous owners just ran the HW off the immersion heater (pressurised hot water tank upstairs) - but the CH off the oil boiler.


I then started investigating and found the wiring on the controller wall plate looks odd:

(Picture deleted as it denied me posting - will try below)

There's a 3 core and a 4 core wire running to the wall plate - the 3 core has only the L connected and the E/N tucked away. The 4 core is wired corrected to the N/L but then the 2 black wires are connected to HW ON and CH ON - with nothing to the OFF terminals.


There is also a wired thermostat elsewhere in the house, which just has 2 wires connected.


Does anyone have any idea what's going on?

 

[Riley]

Welcome along, Post some pictures via Dropbox and we'll try an decipher it for you

 

[Mattt]

It's not letting me post up a link to the picture unfortunately!

Essentially the wallplate looks like below (numbers of wires in each terminal written below):

N L 1 2 3 4
1 2 0 0 1 1

 

[rpm]

Welcome to the forum Matt.
Good people here to help you.

 

[Mattt]

Here's a Dropbox link: https://www.dropbox.com/sh/vy945kdkf4lz57a/AAArpy3yKoD7NqyR2cvKrx1ha?dl=0

 

[Mattt]

Thanks for the welcomes

 

[stevetheplumber]

you only need the off terminal if your using a three port motorised valve as you say you haver a mains pressure hwc i would assume you have two two port motorised valves so the wiring you have sounds correct

 

[PETE 123]

Live to power on valve, will shut when no power on its own under sprint tension

 

[Mattt]

Thanks, it's a Trianco Contractor boiler.

It was serviced 3 months ago, so a bit puzzled as to what's going on. I recently replaced the old Drayton Tempus 7 controller with the Tado extension kit but the wiring is identical for both.

 

[jtsplumbing]

This is the wiring into the timer, have you found the main wiring centre that everything go's into [valves - stats etc.]