Step Thermostat Processing (Fxtq) - Daikin VRV IV-S RXTQ-TAVJU Series Service Manual

Outline of Control (Indoor Unit)
∗1. Fixing of the fan H tap.
Note:
∗2. The heater backup prohibiting conditions are prioritized. Even when the heater ON conditions
∗3. The operation must continue for a certain period of time after the heater turns OFF.

6.12 4 Step Thermostat Processing (FXTQ)

[Outline]
The thermostat ON/OFF for the indoor unit is controlled in accordance with [Thermostat Step 1].
The heater ON/OFF operation during heating is controlled in accordance with [Thermostat Step 2,
3, or 4] or [Thermostat Step 1, 2, or 3].
For more details of the heater, see "6.11 Heater Control (FXTQ)".
[Detail]
• [Thermostat step 1] = "OFF"
• [Thermostat step 2] = "OFF"
• [Thermostat step 3] = "OFF"
• [Thermostat step 4] = "OFF"
(1) Cooling
ON
[Thermostat step 2]
OFF
2˚C (3.6˚F)
[Thermostat step 1]
ON
OFF
1°C (∗1) 1°C (∗1)
(1.8°F)
(1.8°F)
Set temperature
∗1. This value varies according to the field setting
Note:
69
Condition A
• Heating mode
• Thermostat step 1 = "ON"
• Not during fan residual operation
&
OR
&
• Hot-water heater = "1" (ON)
Condition B
• Elimination of Condition A
• Indoor unit error [Stop due to error]
• Indoor unit error [Abnormal stop]
OR
• Indoor unit error [Remote control thermistor error]
• Indoor unit error [Suction air thermistor error]
• During defrosting or oil return operation
are met, the heater is turned OFF when the prohibiting conditions are met.
4. The thermostat steps for this control comply with the "6.12 4 Step Thermostat Processing
(FXTQ)".
• Drain pump abnormal output = OFF
• Thermostat OFF error has not occurred.
• Forced thermostat OFF = "0" (OFF)
• Normal operation = ON
&
• Remote control operation mode = "Heating"
OR
• Not during anti-freeze operation
Elimination conditions of the above
4˚C (7.2˚F)
Controlled temperature
• [Electrical heater setting] = "01"
• [Electrical heater setting] = "03"
Perform the processing
in the following chart.
(2) Heating
ON
[Thermostat step 4]
OFF
ON
[Thermostat step 3]
OFF
ON
[Thermostat step 2]
OFF
ON
[Thermostat step 1]
OFF
Heater backup prohibiting
conditions (∗2)
1.5˚C (2.7˚F) 1.5˚C (2.7˚F)
1.5˚C (2.7˚F) 1.5˚C (2.7˚F)
<Ttsoff>
<Ttson>
1°C (∗1) 1°C (∗1)
Controlled
temperature
(1.8°F) (1.8°F)
Set temperature
Functions and Control
SiUS331604E