Daikin GQI-Eco Series Service Manual page 54

Function Details
3.2.8 General Electronic Expansion Valve Control
When cooling/heating, PI control of electronic expansion valve is conducted to keep the heat
exchanger outlet subcooling degree constant.
•
•
*
3.2.9 Hot Start Control (Only in Heating Operation)
In heating, when performing a startup, or after the defrosting cycle has been completed, the
indoor fan will be controlled in order to prevent cold air draft and secure the starting
performance (quick pressure build-up).
40
Target heat exchanger outlet subcooling degree > actual heat exchanger outlet subcooling
degree
 The electronic expansion valve will close.
Target heat exchanger outlet subcooling degree < actual heat exchanger outlet subcooling
degree
 The electronic expansion valve will open.
The value of target heat exchanger outlet subcooling degree varies depending on change of
discharge pipe superheat degree of inverter compressor, etc.
Indoor unit fan: OFF
Heating operation is turned ON with remote controller.
Indoor unit fan: LL tap
(
&
Indoor unit fan: L tap
(
&
Indoor unit fan: M tap
(
&
Indoor unit fan: Set fan speed
Condition
A Indoor unit heat exchanger temperature > 34°C
Indoor unit heat exchanger temperature > indoor suction
B air temperature +17°C
(+12°C if outdoor air temperature is < 5°C)
Indoor unit heat exchanger temperature > indoor suction
C air temperature +22°C
(+20°C if outdoor air temperature is < 5°C)
• 1 minute elapsed with LL tap
(
• Condition A is met.
• Condition B is met.
OR
• 3 minutes elapsed after compressor startup
• 1 minute elapsed with L tap
(
• Condition A is met.
• Condition B is met.
OR
• 5.5 minutes elapsed after compressor startup
(Continuing L tap on indoor unit without M tap equipped)
• 1 minute elapsed with M tap
(
• Condition A is met.
• Condition C is met.
OR
• 10.5 minutes elapsed after compressor startup
ESIE15-13B
Function and Control