520 Indoor / 520 Outdoor Service Manual
Ver. 1.00
72
CONFIDENTIAL
12-9. Multi-unit system ON/OFF conditions
In an Easy-Link system, the amount of 520 Indoors or 520 Outdoors called on to activate depends on the
FLOW RATE
and the
SET TEMPERATURE.
1.
Condition required to activate an additional 520 Indoors or 520 Outdoors:
Flow rate required to activate additional 520 Indoors or 520 Outdoors= A × n
Where
n
= number of currently activated 520 Indoors or 520 Outdoors
and
A
is dependent factor of the set temperature. See table below:
Set temperature
Factor “A"
˚
F
˚
C
GPM
L/min
100 – 120
38 - 49
3.4
13
125,130
52 - 54
3.2
12
140
60
2.9
11
145,150
63 - 65
2.6
10
155 – 185
68 - 85
2.4
9
2. Condition required to reduce the number of activated 520 Indoors or 520 Outdoors:
A. In the case of reducing down from two unit of 520 Indoors or 520 Outdoors to one units
of 520 Indoor or 520 Outdoor: Flow rate = A / 1.7
B. All other cases: Flow rate = A × (n - 2)
3. Example: Set temperature = 120
˚
F in a four unit system and priority unit is No. 1
To activate additional
520 Indoors or 520 Outdoors
To reduce number of activated
520 Indoors or 520 Outdoors
Unit No.
Flow rate
Unit No.
Flow rate
GPM
L/min
GPM
L/min
No.1 ON
0.5
2.0
No.4 OFF
6.8
25.7
No.2 ON
3.4
12.9
No.3 OFF
3.4
12.9
No.3 ON
6.8
25.7
No.2 OFF
2.0
7.6
No.4 ON
10.2
38.6
No.1 OFF
0.4
1.4
