Absolutely you do for it to work. The control box is the brains it is
also a connection to the internet so that you can manage your boiler
from your phone. There are other great features like turning off the
heating when you go out.... because it kno...
And to try and be clear... The wires you show are literally going to an
on - off switch controlled by the thermostat but the thermostat requires
power so there should be a positive and neutral wire as a power supply
going to as well. If it is connect...
You either need a 4 wire run to the thermostat as it requires power or a
stand for your thermostat (which provides power) and it will connect
wirelessly to the nest control box. I have a boiler that just requires
the 2 wires as well. The control box ...
