3
1
5
• VRV Systems • Outdoor Units
62
• Outdoor Units • VRV HEAT PUMP • RXYHQ12-36P(8)
5
Capacity tables
5 - 4
Capacity correction factor
RXYHQ18,26,28,30P
Correction ratio for cooling capacity
Correction ratio for heating capacity
3TW31472-1
NOTES
1
These figures illustrate the correction ratio for piping length in capacity for a standard indoor unit system at maximum load (with the thermostat set to maximum)
under standard conditions. Moreover, under partial load conditions, there is only a minor deviation for the capacity correction ratio, shown in the above figures.
2
With this outdoor unit, constant evaporating pressure control when cooling and constant condensing pressure control when heating is carried out.
3
Method of calculating the capacity of the outdoor units.
The macimum capacity of the system will be either the total capacity of the indoor units or the macimum capacity of the outdoor units as mentioned below,
whichever is smaller.
Condition: Indoor connection ratio does not exceed 100%
Maximum capacity of outdoor units = Capacity of outdoor units from capacity table at 100% connection ratio X Correction ratio of piping to farest indoor
Condition: Indoor connection ratio exceeds 100%
Maximum capacity of outdoor units = Capacity of outdoor units from capacity table at installed% connection ratio X Correction ratio of piping to farest indoor
4
When level difference is 50m or more and equivalent pipe length is 90m or more, the diameter of the main gas and liquid pipes (outdoor unit - branch sections)
must be increased. For new diameters, see below.
5
When the pipe length after the first refrigerant branch kit is more than 40m, pipe size between first and final branch kit must be increased (refer also to
installation manual).
6
Equivalent length used in the above figures is based upon the following equivalent length
equivalent piping length =
equivalent length of main pipe X correction equivalent length of branch pipes x correction factor
Choose the correction factor from the following table.
When cooling capacity is calculated: gas pipe size
When heating capacity is calculated: liquid pipe size
Example
In the above case:
(Cooling) Overall equivalent length= 80mx1.0 + 40mx1.0 = 120m
(Heating) Overall equivalent length= 80mx0.5 + 40mx1.0 = 80m
The rate of change in:
Cooling capacity when height difference = 0 is thus approximately 0.83
Heating capacity when height difference = 0 is thus approximately 1.0
0
-10
10
1.00
1.00
0.98
0.98
0.96
0.96
0.94
0.94
0.92
0.90
0.88
0.86
0.84
0.82
0.80
0.78
0.92
0.90
0.88
0.86
0.84
0.82
0.80
0.78
20
30
40
50
60
20
40
60
80
100
120
140
160
180
-20
-30
-40
-50
Equivalent piping length (m)
H
eight
diff
erence bet
ween out
door
and
far
es
t i
ndoor
(m
)
1.00
0
10
-10
10
20
30
40
50
60
70
80
90
100
110
-10
-20
-40
-50
20
30
40
50
60
1.00
Equivalent piping length (m)
Model
gas
liquid
RXYHQ18P
31.8
19.1
RXYHQ26-30P
38.1
22.2
Model
gas
liquid
RXYHQ18P
28.6
15.9
RXYHQ26-30P
34.9
19.1
Correction factor
Standard size
Size increase
Cooling (gas pipe)
1.0
0.5
Heating (liquid pipe)
1.0
0.5
Main gas pipe size increase
Main liquid pipe size increase
Branch gas pipe size increase
Branch liquid pipe size increase
Height
dif
ference
be
tw
een out
door and
far
es
t i
ndoo
r (
m
)
