Advice on replacing Thermostat Controls

[thecourtenayboy]

Hi all, we recently move house and the central heating controls need replacing as there is no thermostat and only way to control HW or CH is manually on or off and the the 1-5 dial on the boiler.

I bought a Hive Active Heating kit for the system, which is a traditional vented tank system. Unfortunately though, what should have been a simple swap is actually more complicated.

The wiring of the existing Controller and the Hive are exactly the same. However there is no cable connected to 2, which should be CH OFF. It looks like the previous owner has adjusted the wiring to allow the system to be controlled manually without a thermostat and prevent the controller from turning the CH off.

So I know where to connect the L, N, 1, 3, 4 cables but I don’t know which to connect to number 2. There are two red cables that are loose in the back box, one is labelled Spare Loop. Does anyone have any suggestions on how to figure out which cable should connect to number 2? Perhaps with a multimeter?

https://ibb.co/DMJmK9K
https://ibb.co/ryHHczX
https://ibb.co/1JhBHPc

 

[CBW]

CH off isn’t needed in either setup, and is rarely used. You have a Y plan (3 port mid position valve), so you do need hot water off.

 

[ianmcd]

as @CBW ABOVE chOFF IS NOT USED

 

[thecourtenayboy]

Thanks @CBW & @ianmcd

Wired it up as suggested and all working fine