This new thermostat is suitable for fan-coil system. It has a port to control a three-speed fan. At the same time, it can control a 2-pipe or 4-pipe FCU. It can expand functions such as room card, window card, and analog (0-10V) Output, MODBUS control, etc. https://www.thermostat-hotowell.com/thermostat/fan-coil-thermostat/hvac-wifi-thermostat.html