Cooling Operation Fan Control - Daikin VRV III-S RXYMQ36 48PVJU Service Manual

SiUS34-907
2.4

Cooling Operation Fan Control

In cooling operation with low outdoor air temperature, this control is used to provide the adequate amount of
circulation air with liquid pressure secured by high pressure control using the outdoor unit fan.
When the outdoor temperature ≥ 68°F, the compressor will run in Step 7 or higher.
When the outdoor temperature ≥ 64°F, it will run in Step 5 or higher.
When the outdoor temperature ≥ 54°F, it will run in Step 1 or higher.
-1 step on
outdoor unit fan
Fan Steps
Cooling
STEP 0
STEP 1
STEP 2
STEP 3
STEP 4
STEP 5
STEP 6
STEP 7
STEP 8
Function
Upper limit of fan
revolutions: STEP 8
Pc < 399 psi
Upper limit of outdoor unit
fan revolutions
STEP 7
PI control
Lapse of 20 sec.
Hold the
current step on
outdoor unit fan
PI control
M1F
M2F
0 rpm 0 rpm
250 rpm
0 rpm
400 rpm 0 rpm
285 rpm 250 rpm
360 rpm 325 rpm
445 rpm 410 rpm
580 rpm 545 rpm
715 rpm 680 rpm
850 rpm 815 rpm
Pc: High pressure sensor detection value
Pc > 470 psi
PI control
+1 step on
outdoor unit fan
Lapse of 20 sec.
Basic Control
35