OpenTherm is a groundbreaking language that enables seamless communication between smart thermostats and boiler heating system. By utilizing OpenTherm, thermostats gain the ability to control both home heating controls and domestic hot water systems simultaneously. This innovation holds tremendous importance, especially considering the limitations of older boilers that lack OpenTherm support. Traditional boilers with simple on or off controls fail to provide the level of efficiency and comfort that modern homeowners seek. These boilers operate by heating the water used to warm your home to a fixed, preset temperature. However, this approach often falls short of meeting individual comfort requirements and can result in unnecessary energy consumption. The introduction of OpenTherm-compatible thermostats and newer boilers has revolutionized the way we control our home heating systems. With OpenTherm, thermostats can now communicate with the boiler, instructing it on when to adjust the heating water temperature and to what extent. This advanced level of control allows the boiler to use more or less gas, depending on the specific temperature set by the thermostat. The benefits of OpenTherm extend beyond mere convenience. By enabling thermostats to regulate the heating water temperature accurately, OpenTherm maximizes energy efficiency. With precise control over the boiler's gas consumption, unnecessary energy waste is significantly reduced. This not only translates to cost savings but also helps reduce environmental impact by minimizing carbon emissions. Moreover, OpenTherm's ability to control both heating and domestic hot water systems simultaneously ensures a harmonious balance between comfort and efficiency. With this technology, homeowners can optimize their heating system's performance based on their unique preferences, resulting in personalized and consistent comfort throughout their living space. WT-20 OT is ETOP featured opentherm boiler thermostat with large LCD display and convenient installation.