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Note On Adding Refrigerant
Note:
The standard pipe length calculated for precharged value for each circuit is 7.5m (25’).
Safety and Leakage Check
CAUTION
• Refrigerant charging must be performed after wiring, vacuuming, and leak testing.
•
DO NOT
exceed the maximum allowable quantity of refrigerant or overcharge the system.
Doing so can damage the unit or impact it’s functioning.
• Charging with unsuitable substances may cause explosions or accidents. Ensure that only the
appropriate refrigerant (R410a) is used.
Refrigerant containers must be opened slowly. Always use protective gear when charging the system.
•
•
DO NOT
mix refrigerants types.
N
=2 (Two Zone models),
N
=3 (Three Zone models), N=4 (Four Zone models), N=5 (Five Zone models).
Depending on the length of connective piping, or the pressure of the evacuated system, you
may need to add refrigerant. Refer to the table below for refrigerant amounts to be added:
Air
E
vacuation
ADDITIONAL REFRIGERANT PER PIPE LENGTH
Connective Pipe
Length
Air Purging
Method
Additional Refrigerant (
R410a)
If total pipe length is less
than N x 7.5m (N x 25’)
Vacuum Pump
Do not add Refrigerant
Vacuum Pump
Liquid Side: Ø 6.35 (Ø 1/4”) 9K, 12K, 18K Indoor Units
For each m of excessive pipe length, add: 15g/m
For each ft. of excessive pipe length, add: 0.16oz/ft
Electrical Safety Check
Perform the electrical safety check after
completing installation. Cover the following
areas:
1. Insulation resistance:
The insulation resistance must be more
than 2M
Ω
.
2. Grounding work:
After finishing grounding work, measure
the grounding resistance by visual detection
and using the grounding resistance tester.
Make sure the grounding resistance is less
than 4
Ω
.
3. Electrical leakage check (performed during
test while unit is on)
During a test operation, after completing
installation, use an electroprobe and
multimeter to perform an electrical leakage
check. Turn off the unit immediately if
leakage is detected. Try and evaluate different
solutions until the unit operates properly.
Gas Leak Check
1. Soapy water method:
Apply a soap-water solution, or a liquid
neutral detergent, on the indoor unit
connection, or outdoor unit connections,
with a soft brush to check for leakage of the
connecting points of the piping. If bubbles
emerge, the pipes are experiencing leakage.
2. Leak detector
Use a leak detector to check for leakage.
NOTE:
The illustration is for example purposes
only. The actual order of A, B, C, D, and E on the
system may be slightly different from the unit
you purchased, but the general shape will remain
the same.
Indoor unit
check point
Outdoor unit
check point
A, B, C, D are points for the four zone type.
A, B, C, D, and E are points for the five zone type.
Fig. 9.4
If total pipe length is more
than N x 7.5m (N x 25’),
calculate the excess length
Liquid Side: Ø 9.52 (Ø 3/8”) 24K Indoor Units
For each m of excessive pipe length, add: 30g/m
For each ft. of excessive pipe length, add: 0.32oz/ft
