72
TROUBLESHOOTING
Symptom
Possible Cause
Action
No LCD d isplay
Thermostat is not being
powered.
Check 24VAC between C and R.
Temperature settings
do not change.
The upper or lower
temperature limits were
reached.
Check temperature set-points.
Check Installer Setup Numbers
0600 or 0610, modify as needed.
The keypad is fully locked.
Check Installer Setup Number
0670 to change keypad locked
options.
Summary of Contents for MST03
Page 1: ...MRCOOL Universal WiFi Thermostat...
Page 2: ......
Page 4: ......
Page 11: ...7 Fig 1 Thermostat Dimensions in inches mm...
Page 12: ...8 Fig 2 Thermostat back case dimensions in inches mm...
Page 13: ...9 Fig 3 Thermostat cover plate dimensions in inches mm...
Page 14: ...10 Fig 4 Selecting thermostat location...
Page 16: ...12 Fig 5 Mounting wall plate...
Page 20: ...16 Fig 7 Inserting wires in terminal block IMPORTANT Use 18 gauge thermostat wire...
Page 35: ...31 Fig 21 Mount thermostat to wall plate...
Page 48: ...44 OPERATION Fig 23 Thermostat Keys Fan Choose fan mode...
Page 49: ...45 Fig 24 Thermostat Display...
Page 64: ...60 Fig 33 Fig 34 4 Press the key on thermostat screen until the flash Fig 35...