How do I connect an expansion unit to my DITRA-HEAT-E-WIFI/-RT/-R thermostat?
How do I connect an expansion unit/power module to the thermostat? What is the maximum length of signal cable between a power module and the thermostat?
Connect thermostat ports A & B to power module ports C & D. See installation guide. The maximum length is 80 feet (25 meters), and with 20 AWG conductors (recommended).