Daikin SkyAir GQI-Eco Series Service Manual page 53

SiBE281013
3.2.19 Low Outdoor Air Temperature Control in Cooling Operation
Controls compressor and outdoor unit fan under low outdoor air temperature condition to secure
pressure difference between high and low pressure.
Hp: High pressure
Lp: Low pressure
Ta: Outdoor air temperature
Tfin: Inverter fin temperature
&
OR
&
Hp < 1.57MPa
&
Frequency Restriction
Function and Control
Hp-Lp < 0.93MPa
OR
Compression ratio < 2.1
Hp < 1.86MPa
Ta < 25˚C
Compressor operation frequency
restriction (refer to the followings)
Hp-Lp < 0.78MPa
Compression ratio ≤ 1.8
Outdoor unit fan
-1 step/90 sec.
Hp-Lp < 0.78MPa
OR
Compression ratio < 1.8
Hp < 1.57MPa
Tfin < 66˚C
No frequency
restriction
Normal operation
Outdoor unit fan
Outdoor unit fan: Stop
RZQG71LV1B
Lower limit frequency
Ta ≤ 25˚C
Step 11
Upper limit frequency
Ta > 27˚C
Step 17
Function Details
Hp-Lp > 1.08MPa
OR
Hp < 2.94MPa
OR Compression ratio > 2.4
Ta > 27˚C
Outdoor unit fan
+1 step/90 sec.
Hp-Lp > 0.98MPa
&
Compression ratio > 2.2
OR
Hp > 2.25MPa
Step 1
Hp-Lp > 0.88MPa
&
Compression ratio > 2.0
OR
Hp > 1.66MPa
Tfin ≥ 81˚C
RZQG100-140LV1B
Lower limit frequency
Step 9
Upper limit frequency
Step 15
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