Need help understanding details of thermostat wiring scheme
I'm seeing a classic bimetallic thermostat with two control switches and one knob.

I have deleted the outline and colourised it a little.



Terminal 5 connects to the live 240V power

Switch A connects this to terminal 1 when on

Switch C is the bimetallic thermostat and connect terminal 1 to either the hot link or cold link and the anticipator resistor labeled "RF" for some reason (my German isn't very good)

Switch B is the heat/cool selector and connect the output terminal 2 to ether the hot link or the cold link.  

B and C work together like a two-way light swicth, so when both  heat/cool and the temperature selection are in agreement the and the power switch is on output 2 is live.