Installation manual

7
4. Installingtherefrigerantpiping
4.7. PrecautionswhenreusingexistingR22refrigerantpipes
• Refer to the owchart below to determine if the existing pipes can be used and if it is necessary to use a lter dryer.
• If the diameter of the existing pipes is different from the specied diameter, refer to technological data materials to conrm if the pipes can be used.
• If the diameter of the existing gas side pipe is bigger than the specied diameter, turn SW8-1 on.
Fig.4-8
1
Indoor unit
2
Outdoor unit
3
Main piping
4
Branch piping
5
Multi distribution
pipe (option)
Outdoor unit : RP250 A: ø12.7 ... 65 m
Indoor unit 1 : RP71 B: ø9.52
... 5 m
Indoor unit 2 : RP71 C: ø9.52
... 5 m
Indoor unit 3 : RP71 D: ø9.52
... 5 m
Main piping ø12.7 is A = 65 m
Branch piping ø9.52 is B + C + D = 15 m
Therefore, the amount of additional charge is: 65
×
0.12 + 15
×
0.06 -3.6=5.1 (kg)
(Fractions are rounded up)
Max. 1m
Outdoor unit
At time of shipping
(kg)
A+B+C+D
Amount of additional refrigerant charge (kg)
30 m and less 31-40 m and less 41-50 m and less 51-60 m and less 61-70 m and less 71-120 m and less
RP200 6.5
No additional
charge necessary
0.9 kg 1.8 kg 2.7 kg 3.6 kg
Calculate the
amount of additional
refrigerant charge
using formula pro
-
vided below.
RP250 7.1 1.2 kg 2.4 kg 3.6 kg 4.8 kg
Whenlengthexceeds70m
When the total length of the piping exceeds 70 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 charge amount for 70 m”,
perform the additional charge using the amount shown in “Additional charge amount for 70 m”.
Amount of additional
charge
=
Main piping:
Liquid line size
ø12.7 overall length ×
0.12
+
Main piping:
Liquid line size
ø9.52 overall length ×
0.09 (Gas line: ø28.58)
+
Branch piping:
Liquid line size
ø9.52 overall length ×
0.06 (Gas line: ø15.88)
+
Branch piping:
Liquid line size
ø6.35 overall length ×
0.02 (Gas line: ø15.88)
– 3.6 (kg)
(kg) (m) × 0.12 (kg/m) (m) × 0.09 (kg/m) (m) × 0.06 (kg/m) (m) × 0.02 (kg/m)
Additional charge amount
for 70 meters
RP200 3.6 kg
RP250 4.8 kg
* Refer to page 11
The existing pipes cannot be reused.
Use new pipes.
Replacement operation
Theexistingpipethicknessmeetsspeci-
cationsandthepipesarenotdamaged.
Theexistingpipethicknessdoesnotmeet
specicationsorthepipesaredamaged.
Measure the existing pipe thickness and
check for damage.
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
Perform the airtight test, vacuum air purging, ad-
ditional refrigerant charging (if necessary), and
gas leak check.
* 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.
BG79U791K01_en.indd 7 9/18/2007 3:43:20 PM