This sensor is compatible with Positive Input Ventilation (PIV) units DRI-ECO-HEAT-HC and DRI-ECO-NOX-HEAT. The Drimaster-ECO relative humidity sensor (DRI-ECO-RH) works in tandem with the Drimaster-ECO 4 way switch (DRI-ECO-4S) and the Drimaster-ECO CO2 Sensor (DRI-ECO-CO2).
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