This black finish Invita(R) WiFi Thermostat makes upgrading easy by using the existing 2 wires from any living space to connect to an HVAC Interface Module in the mechanical room. It works with most types of heating and cooling systems including conventional, heat pump and dual fuel while offering fan, relative humidity and ventilation control. The Watts(R) Home app provides secure WiFi adjustment, remote temperature control and can send email notifications when there are problems with the HVAC system. The Invita WiFi offers a choice of five display screen color themes.