Carrier 38QUS012D8S Service Manual page 105

Electrical Control Function
The indoor fan runs at auto fan in each mode.
The louver operates the same in each mode.
If the machine switches mode between heating and cooling, the compressor stops for 15 minutes and then
selects a mode again according to T1-Ts.
If the temperature is modified, the machine selects a running function.
1.3.5 Dehumidifier Mode
The indoor fan speed is fixed at breeze and can't be changed.
All protections are activated and operate the same as they do in cooling mode.
1.3.6 Timer Function
1.3.6.1 The timing range is 24 hours.
1.3.6.2 Timer On. The machine turns on automatically at the preset time.
1.3.6.3 Timer Off. The machine turns off automatically at the preset time.
1.3.6.4 Timer On/Off. The machine turns on automatically at the preset On Time, and then turns off
automatically at the preset Off Time.
1.3.6.5 Timer Off/On. The machine turns on automatically at the preset Off Time and then turns off
automatically at the preset On Time.
1.3.6.6 The timer does not change the unit operation mode. If the unit is off now, it does not start up
immediately after the "timer off" function is set. When the setting time is reached, the timer LED switches ioff
and the unit running mode remains unchanged.
1.3.6.7 The timer uses relative time, not clock time.
1.3.7 Sleep Mode
1.3.7.1 The sleep function is available in cooling, heating or auto mode.
1.3.7.2. The operational process in sleep mode is as follows:
When cooling, the temperature rises 1℃(to not higher than 30℃) every hour, 2 hours later the temperature
stops rising and the indoor fan is fixed to low speed.
When heating, the temperature decreases 1℃ (to not lower than 17℃) every hour, 2 hours the temperature
stops decreasing and the indoor fan is fixed at low speed. (Anti-cold wind function takes priority).
1.3.7.3 Sleep mode lasts a maximum of 7 hours. After 7 hours, the unit does not switch off., but for console,
the unit switches off.
1.3.7.4 The timer uses relative time, not clock time.
1.3.8 Auto-Restart Function
The indoor unit has an auto-restart module that allows the unit to restart automatically. The module
automatically stores the current settings (not including the Swing setting) and, in the case of a sudden power
failure, will restore those setting automatically within 3 minutes after power returns.
1.3.9 Drain Pump Control (For Duct and Cassette)
Use the water-level switch to control drain pump.
Electrical Control System 103