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Troubleshooting
• SYMPTOM: The thermostat display flashes ' Occupied 1' when running the
program.
CAUSE: The sensor connected to the Dry Contact terminals of the
thermostat, is active, forcing the unit into ' Occupied 1' .
REMEDY: Verify proper wiring between the thermostat and the occupancy
sensor and verify that the wiring is not shorted. If no sensor is connected,
program the Dry Contact polarity for Normally Open (step #14, page 21 of
the Owner's Manual).
• SYMPTOM: The thermostat will only allow Heat or Off in 2-pipe
installations, even though chilled water is available.
CAUSE: Faulty, improperly wired, or improperly installed H2O changeover
sensor.
REMEDY: Confirm proper wiring of the changeover sensor (between R and
H2O). Confirm proper placement of the sensor (good mechanical coupling
for temperature transfer). Test the changeover sensor as follows:
1. Remove power from the fan coil system.
2. Disconnect the wire between the sensor and the H2O terminal.
3. Place an ohmmeter between R and the wire just disconnected from
the sensor.
4. A good sensor will show continuity whenever the water temperature
is confirmed to be at or below 65 degrees. If the sensor is open when
the water temperature is confirmed to be at or below 65, replace
the sensor.
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