Normal Outdoor Fan Control In Cooling Operation - Daikin Sky Air R-407C Service Manual

Overview of the cooling mode functions
2.5

Normal Outdoor Fan Control in Cooling Operation

1
Applicable units
Purpose
2
Method
3
Different fan
4
speeds
5
Used input
2–32
R(Y)P71-250B
The purpose of this normal outdoor fan control is to ensure a correct discharge pressure in function of
the outdoor air and indoor room temperature.
The table below shows in which conditions the outdoor fan works at low or high speed.
Condition
Ta < 41.7 - 0.84 x Tr
Ta > 45.7 - 0.84 x Tr
Ta = ambient temperature = outdoor air temperature; Tr = room suction temperature.
The table below explains the meaning of L, H and HH fan speed.
71
Fan operation
1 fan
OFF OFF
L L
H H
HH HH
The normal outdoor fan control during cooling operation uses the following inputs:
Input
Indoor room temperature R1T
Outdoor air temperature R1T
Fan Speed
L
H
100 and 125
Upper fan Lower fan
(MF1) (MF2)
OFF OFF
L L
H H
HH HH
Connection on
indoor PCB
X19A
—
ESIE02–01
200 and 250
Fan 1 Fan 2
OFF OFF
H OFF
H H
H H
Connection on
outdoor PCB
—
X4A
Part 2 – Functional Description