The RTS1 wiring is shown here.
As you'll see, it's straightforward. What isn't straightforward is where to connect the wiring to your boiler, and you haven't told us what make and model it is.
the reason i did not say anything about my boiler is my room stat is not working and i want to replace it and i looked at this one and it look's esay to use and i wanted no if it was easy to wire the one i have has 3 wires is that write