Stalus Programmable Thermostats are sold in many different types of units in the United Kingdom and are designed to handle different types of climate control systems. The Stalus RT-500 is installed using only two terminals unless your system is wired for an Earth connection. Mount the unit in the appropriate location on your wall and connect the standard thermostat cable to wire this unit in the United Kingdom.
Pull the thermostat cable wire through the back plate of the Stylus thermostat. Mount the thermostat to the wall as directed per instructions. Read the wiring diagram on the thermostat.
Connect the main power wire from the cable to the L terminal, tightened under the brass connector on the terminal. This wire supplies power to the unit.
Connect the output wire on the cable to the SL terminal securely with the brass connector. The SL (Switched Live) output supplies power to the climate control system at preset programmed intervals.
Connect the Earth wire from the cable, if provided, to the terminal marked Earth. This connection is not necessary for the safe operation of this unit but this is the only terminal the Earth wire should go to, if so wired.
Consult a HVAC professional if you are unsure of the colour coded wiring you have in your home.