The TS-2 thermostat stations is designed to replace a thermostat connected to a standard HVAC unit. The TS-2 can be used to control most HVAC systems including heat pump and multi-stage HVAC systems. The  TS-2 is wired to the HVAC system using the same low-voltage thermostat cable, and has the standard color-coded wiring as most thermostats. The Hydro-x allows separate Day and Night settings for each of up to (4) TS  modules, so multiple HVAC systems can be controlled by a single Hydro-X system. The TS-2 also has an adjustable delay time for each HVAC systems being activated. That minimizes high start-up (inrush current) and allows up to 4 HVAC systems to be safely controlled. LCD Display, Easy Operation Seamless Connection with Hydro-X Micro-SD for Firmware Upgrade Address Assignment Plug & Play