The two red wires are connected to an end line switch, which closes when the
valve is fully opened. Those two wires close a low voltage circuit to start
the circulator. The two yellow wires are the valve's motor. One of them gets
connected to one leg of your 24 volt transformer, the other one gets
connected to the return wire from its thermostat, the second wire from the
thermostat and the second leg of the transformer get wire nutted together.
Since you have two zone valves, just duplicate the process
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