The junction box was not intended to be used with the Tower mid-position valve. It needs to be replace by a standard 10 position wiring centre. Here is the basic wiring diagram, which needs modifying as follows:
1. Ignore the room stat (it's built into the Hive)
2. Link 4 to 5
3. The Hive replaces the Time controller and wired as follows:
L to 1
N to 2
1 to 7
2 not used
3 to 6
4 to 4
The boiler has pump overrun, so you need to follow the diagram on the left.
The Hive relay box will need to be near the pump and valve, probably upstairs.
There will be five wires between the junction box and the boiler: Live (1), Neutral (2), Earth (3), Pumped Live (9) and Switched Live (10).
The Pumped live wire connects to PL terminal in the boiler.
The switched live wire connects to ON terminal in the boiler.
Make sure that there is no link between HW and ON in the boiler.
The boiler timer needs to be disconnected, but left in place.
The off/timed/continuous switch is redundant
The CH/CH+HW switch is redundant
The Hi/Lo switch will still work
Neutral and Earth for the pump should be connected locally (terminals 2 &3 of junction box); there is no need to connect directly to the boiler.
It is important that there is only one source of electricity for the heating system. Do not take a supply for the boiler from a socket downstairs and use a separate source for upstairs, i.e the Hive relay box.