Hi all, new here today, quick question that has probably been answered and sounds idiotic... I live in N.I, I have an oil burner outside and an old pin dial style with a little clock in the middle thermostat in the utility room next to the kitchen. Hot water tank is gravity fed and downstairs, I have an emersion switch next to the boiler and a fireplace with back boiler. Question is, is the thermostat basically just an on off switch with a timer ? Could the nest, just replace this in the utility room and have the actual controller in the living room plugged into the wall. When I switch the heating on it warms the water in the water tank for hot water aswell as the radiators and I don't have control of temp on the hwt nor do I care So, can the nest link go on the wall where the old thermostat is ?...sorry I've no clue. Pic of old thermostat attached.