89
18.2.8. Evacuation after Servicing the Outdoor
Unit Refrigeration Circuit
18.2.8.1 Evacuation of the Complete
Refrigeration Circuit, Indoor and Outdoor
Unit
•
Confirm that both the 2-way and 3-way valves are
set to the opened position.
•
Connect the vacuum pump to 3-way valve’s service
port.
•
Evacuation for approximately one hour. Confirm
that the compound meter indicates - 0.1Mpa (500
Microns / 29.9 in. hg).
•
Close the valve (Low side) on the charge set, turn
off the vacuum pump, and confirm that the gauge
needle does not move (approximately 5 minutes after
turning off the vacuum pump).
• Disconnect the charge hose from the vacuum pump.
18.2.8.2 Refrigerant Charging
•
Connect the charge hose to the charging cylinder,
open the 2-way valve and the 3-way valve.
•
Connect the charge hose which you disconnected
from the vacuum pump to the valve at the bottom
of the cylinder. If the refrigerant is R410A, make the
cylinder bottom up to ensure liquid charge.
• Purge the air from the charge hose
•
Open the valve at the bottom of the cylinder and
press the check valve on the charge set to purge the
air (be careful of the liquid refrigerant).
•
Put the charging cylinder onto the electronic scale
and record the weight.
• Open the valves (Low side) on the charge set and
charge the system with liquid refrigerant. If the
system cannot be charge with the specified amount
of refrigerant, or can be charged with a little at a time
(approximately 150g each time) , operating the air
conditioner in the cooling cycle; however, one time is
not sufficient, wait approximately 1 minute and then
repeat the procedure.
•
When the electronic scale displays the proper weight,
disconnect the charge hose from the 3- way valve’s
service port immediately
•
If the system has been charged with liquid refrigerant
while operating the air conditioner, turn off the air
conditioner before disconnecting the hose.
• Mounted the valve stem caps and the service port.
Use torque wrench to tighten the service port cap to
a torque of 18N·m (13.27 ft·lbs).
•
Always leak check after servicing the refrigerant
system.
There are one low-pressure centralized valve and one high-
pressure centralized valve, it will be more time saving when
vacuum and recycle refrigerant. But refer to the previous
instruction when vacuum and recycle refrigerant.
19. Electronic Function
19.1. Abbreviations
• T1: Indoor ambient temperature
• T2: Middle indoor heat exchanger coil temperature
• T2B: Indoor heat exchanger exhaust coil temperature
(located on the outdoor unit)
• T3: Outdoor heat exchanger pipe temperature T4:
Outdoor ambient temperature
• T5: Compressor discharge temperature
19.2. Electric Control Working
Environment.
• Input voltage: 230V.
•
Input power frequency: 60Hz.
• Indoor fan standard working amp.: <1A
• Outdoor fan standard working amp.: <1.5A.
•
Four-way valve standard amp.: <1A
20. Start-Up
20.1. Adding Refrigerant - Single-Zone
Systems
The outdoor unit is factory-charged with refrigerant. Calculate
the additional refrigerant required according to the diameter
and the length of the liquid pipe between the outdoor unit
and indoor unit connections.
Be sure to add the proper amount of additional refrigerant.
Failure to do so may result in reduced performance.
NOTE:
Interconnecting pipe work between outdoor and
indoor units must be 10 ft. or longer.
NOTE:
Do not remove refrigerant for line lengths less
than 25 ft. R-410A is a blended refrigerant. If you
must remove charge, it is necessary to remove
the entire charge and weigh in the new charge.
Table 19. Adding Refrigerant
System Size
(KBtu)
Pipe Length
Amount of Refrigerant
to add
09
>25 ft. (7.5m)
0.161 oz/ft (15g/m)
12
>25 ft. (7.5m)
0.161 oz/ft (15g/m)
18
>25 ft. (7.5m)
0.161 oz/ft (15g/m)
24
>25 ft. (7.5m)
0.322 oz/ft (30g/m)
36
>25 ft. (7.5m)
0.322 oz/ft (30g/m)
48
>25 ft. (7.5m)
0.322 oz/ft (30g/m)
