The TS-1 thermostat stations is designed to replace a thermostat connected to a conventional cool only HVAC unit. The TS-1 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.