Index; Troubleshooting: 7 Day Programmables; Troubleshooting: Touchscreens - Daikin TSTATD4271C Installation And Maintenance Manual

Index

Troubleshooting: 7 Day Programmables

• Symptom: The air conditioning does not attempt to
turn on.
Cause: The compressor timer lockout may prevent the
air conditioner from turning on for a period of time.
Remedy: Consult the Owner's Manual in the Installer
Setup section to defeat the Cycles Per Hour (page 21).
• Symptom: The display is blank.
Cause: Lack of proper power.
Remedy: Make sure the power is on to the furnace 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 21).
• 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 21).
• Symptom: When controlling a residential heat pump, and
asking for cooling, the heat comes on.
Cause: The thermostat reversing valve jumper 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 jumper is configured
for "HP" and the HVAC unit is a Gas/Electric.
Remedy: Set the equipment jumper for "Gas".
• Symptom: When the Program button is pressed, the
display reads "DISABLED".
Cause: Program mode is set to "NON PROGRAM".
Remedy: Set Program Mode (Setup 1) to 1, 5/2, or 7
Day. See Selecting Your Program Mode (page 20).
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Troubleshooting: Touchscreens

• 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.
• 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 30).
• 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 30).
• 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.
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