Venstar ColorTouch T8800, Owner'S Manual & Installation Manual

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Troubleshooting
• SYMPTOM: The thermostat touchscreen buttons are not responsive.
CAUSE: The touchscreen is out of calibration.
REMEDY: Remove the thermostat from the backplate. Push the
thermostat back onto the backplate, while keeping your finger pressed
firmly against the center of the touchscreen, until the Calibration screen
appears. Re-calibrate the touchscreen. See Touch Calibration section of
full user’s manual (page 23).
• SYMPTOM: The display is blank.
CAUSE: Lack of proper power.
REMEDY: Make sure the power is on to the HVAC and that you have
24vac between R & C.
• SYMPTOM: The air conditioning does not attempt to turn on.
CAUSE: The cooling setpoint is set too high.
REMEDY: Lower the cooling setpoint or lower the cooling set-point
limit. See Setpoint Limits (page 33).
• SYMPTOM: The heating does not attempt to turn on.
CAUSE: The heating setpoint is set too low.
REMEDY: Raise the heating setpoint or raise the heating set-point limit.
See Setpoint Limits (page 33).
• SYMPTOM: When controlling a residential heat pump, and asking for
cooling, the heat comes on.
CAUSE: The thermostat reversing valve dip switch is set for “B”.
REMEDY: Set the reversing valve jumper for “O”.
• SYMPTOM: When calling for cooling, both the heat and cool come on.
CAUSE: The thermostat equipment dip switch is configured for “HP”
and the HVAC unit is a Gas/Electric.
REMEDY: Set the equipment dip switch for “Gas”.
• SYMPTOM: Air handler control board fuse blows when thermostat
is attached to backplate with power on, but does not blow until the
thermostat is placed onto the backplate.
CAUSE: The Outdoor sensor and/or sensor wiring is shorted.
REMEDY: Check/replace Outdoor sensor and/or sensor wiring.