Automatic Operation - Daikin Super Multi NX FFQ25B8V1B Service Manual

SiBE121021_C
1.7

Automatic Operation

Outline Automatic Cooling / Heating Function
When the AUTO mode is selected with the remote controller, the microcomputer automatically
determines the operation mode as cooling or heating according to the room temperature and
the set temperature at start-up, and automatically operates in that mode.
The unit automatically switches the operation mode to maintain the room temperature at the set
temperature.
Detail
1. The set temperature (Ts) determines the target temperature (Tt).
2. The target temperature (Tt) is calculated as;
3. Thermostat ON/OFF point and mode switching point are as follows.
4. During initial operation
Wall Mounted Type: FTXG and CTXG Series, FTXS Series 60/71 Class
Other Models
Function and Control
Ts: set temperature (set by remote controller)
Tt: target temperature (determined by microcomputer)
Tr: room thermistor temperature (detected by room temperature thermistor)
C: correction value
(Ts = 18 ~ 30°C).
Tt = Ts + C
where C is the correction value
C = 0°C
Tr means the room thermistor temperature.
(1) Heating → Cooling switching point:
Tr ≥ Tt + 3.0°C (wall mounted type: FTXG and CTXG series, FTXS series 60/71 class)
Tr ≥ Tt + 2.5°C (other models)
(2) Cooling → Heating switching point:
Tr < Tt – 2.5°C
(3) Thermostat ON/OFF point is the same as the ON/OFF point of cooling or heating
operation.
Tr ≥ Ts: Cooling operation
Tr < Ts: Heating operation
Target temperature – 2.0˚C
= Thermostat OFF
Target temperature – 2.5˚C
Ex: When the target temperature is 25°C
Cooling → 23°C: Thermostat OFF → 22°C: Switch to heating
Heating → 27°C: Thermostat OFF → 28°C: Switch to cooling
Target temperature – 2.0˚C
= Thermostat OFF
Target temperature – 2.5˚C
Ex: When the target temperature is 25°C
Cooling → 23°C: Thermostat OFF → 22°C: Switch to heating
Heating → 26.5°C: Thermostat OFF → 27.5°C: Switch to cooling
.
Cooling Operation
Target temperature + 3.0˚C
Target temperature + 2.0˚C
= Thermostat OFF
Heating Operation
Cooling Operation
Target temperature + 2.5˚C
Target temperature + 1.5˚C
= Thermostat OFF
Heating Operation
Function of Indoor Unit (RA Models)
(R11892)
(R11893)
91