Use separate moisture inputs and the shared sensor-heating connections.
The ETO2 manual supports one or two ETOR gutter sensors in a one-zone electric-heating system. For a two-zone ETOR system, use one sensor for each zone. The outdoor ETF temperature sensor supplies the ambient-temperature measurement.
For the ETO2 terminal layout in the linked manual:
- Terminals 11–12: brown/green sensor-heating connections for sensors 1 and 2.
- Terminals 15–16: yellow/white moisture input for sensor 1.
- Terminals 19–20: yellow/white moisture input for sensor 2.
- Terminals 31–32: outdoor ETF temperature sensor.
- The ETOR arrangement does not use the pink and grey temperature conductors.
Use the complete one-zone or two-zone diagram and matching controller configuration. Do not put both moisture-sensing pairs on one input merely because the heating circuit is shared. A qualified installer must isolate power before wiring and verify the exact sensor/controller labels.
Sources: ETO2 installation manual (pages 5–9 and Figure 7) and ETOR-55 instructions.