8
Perform the airtight test, vacuum air purging,
additional refrigerant charging (if necessary),
and gas leak check.
4. Installing the refrigerant piping
4.7. Precautions when reusing existing R22 refrigerant pipes
• Refer to the
ß
owchart below to determine if the existing pipes can be used and if it is necessary to use a
Þ
lter dryer.
• If the diameter of the existing pipes is different from the speci
Þ
ed diameter, refer to technological data materials to con
Þ
rm if the pipes can be used.
"
"
"
"
"
"
"
Measure the existing pipe thickness and
check for damage.
The existing pipe thickness meets speci
Þ
ca-
tions and the pipes are not damaged.
Check if the existing air conditioner can operate.
After operating the cooling system for about 30
minutes, do a pump down work.
Disconnect the existing air conditioner from the
pipes.
Attach the new air conditioner
Test run
* Refer to 7.2.
The existing pipes cannot be reused.
Use new pipes.
* If the existing air conditioner cannot operate, use
a refrigerant recovery device to collect the refrigerant.
* In case existing pipes were used for gas or oil
heat pump systems, be sure to clean the pipes.
The existing pipe thickness does not meet
speci
Þ
cations or the pipes are damaged.
Fig. 4-9
Indoor unit
Outdoor unit
Main piping
Branch piping
Multi distribution
pipe (option)
Outdoor unit : HRP200 A: ø9.52 ... 65 m
Indoor unit 1 : RP60 B: ø9.52 ... 5 m
Indoor unit 2 : RP60 C: ø9.52 ... 5 m
Indoor unit 3 : RP60 D: ø9.52 ... 5 m
Main piping ø9.52 is A = 65 m
Branch piping ø9.52 is B + C + D = 15 m
Therefore, the amount of additional charge is: 65 × 0.14 + 15 × 0.05 - 4.3 = 5.6 (kg)
(Fractions are rounded up)
M
a
x
.
1
m
When length exceeds 50 m for twin / triple / quadruple combination (Only HRP200)
When the total length of the piping exceeds 50 m, calculate the amount of additional charge based on the following requirements.
Note: If the calculation produces a negative number (i.e. a “minus” charge), of if calculation results in an amount that is less than the “Additional charage amount for 50 m”,
perform the additional charge using the amount shown in “Additional charge amount for 50 m”.
Amount of additional
charge
=
Main piping:
Liquid line size
ø12.7 overall length ×
0.17
+
+
+
–
4.3 (kg)
(kg)
(m) × 0.17 (kg/m)
Additional charge amount
for 50 meters
1.8 kg
Main piping:
Liquid line size
ø9.52 overall length ×
0.14 (Gas line: ø25.4)
(m) × 0.14 (kg/m)
Branch piping:
Liquid line size
ø9.52 overall length ×
0.05 (Gas line: ø15.88)
(m) × 0.05 (kg/m)
(m) × 0.02 (kg/m)
Branch piping:
Liquid line size
ø6.35 overall length ×
0.02
01̲RG79D564H02̲EN.indd 8
2009/08/26 8:34:17
