37
Page 34
Air Evacuation
Note on Adding Refrigerant
Some systems require additional charging depending on pipe lengths. The standard pipe length varies
according to local regulations. For example, in North America, the standard pipe length is 7.5m (25’).
In other areas, the standard pipe length is 5m (16‘). The refrigerant should be charged from the service
port on the outdoor unit’s low pressure valve. The additional refrigerant to be charged can be
calculated using the following formula:
CAUTION
DO NOT
mix refrigerant types.
For R290 refrigerant unit, the total amount of refrigerant to be charged is no more than:
387g(<=9000Btu/h), 447g(>9000Btu/h and <=12000Btu/h), 547g(>12000Btu/h and <=18000Btu/h),
632g(>18000Btu/h and <=24000Btu/h)
.
ADDITIONAL REFRIGERANT PER PIPE LENGTH
Connective Pipe
Length (m)
Air Purging
Method
Additional Refrigerant
< Standard pipe length Vacuum Pump
N/A
> Standard pipe
length
Vacuum Pump
Liquid Side: Ø 6.35 (ø 0.25”)
R32:
(Pipe length – standard length) x 12g/m
(Pipe length – standard length) x 0.13oZ/ft
R290:
R290:
(Pipe length – standard length) x 10g/m
(Pipe length – standard length) x 0.10oZ/ft
Liquid Side: Ø 9.52 (ø 0.375”)
R32:
(Pipe length – standard length) x 24g/m
(Pipe length – standard length) x 0.26oZ/ft
(Pipe length – standard length) x 18g/m
(Pipe length – standard length) x 0.19oZ/ft
R410A:
R410A:
(Pipe length – standard length) x 15g/m
(Pipe length – standard length) x 0.16oZ/ft
(Pipe length – standard length) x 30g/m
(Pipe length – standard length) x 0.32oZ/ft
R22:
(Pipe length – standard length) x 20g/m
(Pipe length – standard length) x 0.21oZ/ft
R22:
(Pipe length – standard length) x 40g/m
(Pipe length – standard length) x 0.42oZ/ft
Page 35
Electrical and
Gas Leak Checks
Electrical Safety Checks
After installation, confirm that all electrical wiring
is installed in accordance with local and national
regulations, and according to the Installation
Manual.
BEFORE TEST RUN
Check Grounding Work
Measure grounding resistance by visual detection
and with grounding resistance tester. Grounding
resistance must be less than 0.1
Ω
.
Note:
This may not be required for some
locations in the US.
DURING TEST RUN
Check for Electrical Leakage
During the
Test Run,
use an electroprobe and
multimeter to perform a comprehensive electrical
leakage test.
If electrical leakage is detected, turn off the unit
immediately and call a licensed electrician to find
and resolve the cause of the leakage.
Note:
This may not be required for some
locations in the US.
Gas Leak Checks
There are two different methods to check for gas
leaks.
Soap and Water Method
Using a soft brush, apply soapy water or liquid
detergent to all pipe connection points on the
indoor unit and outdoor unit. The presence of
bubbles indicates a leak.
Leak Detector Method
If using leak detector, refer to the device’s
operation manual for proper usage instructions.
AFTER PERFORMING GAS LEAK CHECKS
After confirming that the all pipe connection
points DO NOT leak, replace the valve cover on
the outside unit.
WARNING – RISK OF
ELECTRIC SHOCK
ALL WIRING MUST COMPLY WITH LOCAL
AND NATIONAL ELECTRICAL CODES,
AND MUST BE INSTALLED BY A LICENSED
ELECTRICIAN.
Before Test Run
Only perform test run after you have completed
the following steps:
•
Electrical Safety Checks
– Confirm that
the unit’s electrical system is safe and
operating properly
•
Gas Leak Checks
– Check all flare nut
connections and confirm that the system is
not leaking
•
Confirm that gas and liquid (high and low
pressure) valves are fully open
A: Low pressure stop valve
B: High pressure stop valve
C& D: Indoor unit flare nuts
Check-point of indoor unit
Check-point of outdoor unit
A
B
C
D
Electrical and Gas Leak Checks
