Outdoor unit stop valve
Do not apply two spanners
at this position. If applied,
leakage will occur.
Stop valve
Flare nut
!
C A U T I O N
•
At the test run, fully open the spindle.
•
If not fully opened, the devices will be damaged.
•
Do not attempt to turn service valve rod beyond its stop.
•
Do not loosen the stop ring. If the stop ring is loosened, it is danger
-
ous since the spindle will hop out.
•
An excess or a shortage of refrigerant is the main cause of trouble
to the units. Charge the correct refrigerant quantity according to the
description of label at the inside of service cover.
•
Check for refrigerant leakage in detail. If a large refrigerant leakage
occurs, it will cause difficulty with breathing or harmful gases would
occur if a fire was being used in the room.
Evacuation and refrigerant charge
-
Connect the gauge manifold using charging hoses with a
vacuum pump or a nitrogen cylinder to the check joints of
the liquid line and the gas line stop valve.
-
Check for any gas leakage at the flare nut connection, by
using nitrogen gas to increase the pressure at 4.15 MPa
for outdoor units inside of the field-supplied piping.
-
Operate the vacuum pump for 1 to 2 hours until the
pressure decreases lower than a pressure of 756 mmHg
in vacuum.
-
For charging refrigerant, connect the gauge manifold
using charging hoses with a refrigerant charging cylinder
to the check joint of the liquid line stop valve.
-
Charge the proper quantity of refrigerant according to
the piping length (Calculate the quantity of the refrigerant
charge).
-
Fully open the gas line stop valve, and slightly open the
liquid line stop valve.
-
Charge refrigerant by opening the gauge manifold valve.
-
Charge the required refrigerant within the difference
range of ±0.5kg by operating the system in cooling.
-
Fully open the liquid line stop valve after completing
refrigerant charge.
-
Continue cooling operation for more than 10 minutes to
circulate the refrigerant.
Example of Evacuation and Refrigerant Charge.
Never use the refrigerant charged in the outdoor unit for air purging.
Insufficient refrigerant will lead to failure
Gauge
manifold
Vacuum pump
Nitrogen cylinder for air
tight test and nitrogen blow
during brazing
Gas line stop valve
Liquid line stop valve
Gas line
Liquid line.
Cover the liquid line
with thermal insulation
Cover the flare nut and unit
of the piping connection with
thermal insulation.
Thermal insulation finishing
Wind tape from outside of thermal
insulating of gas piping and liquid
piping
Indoor unit
Insulate the liquid pipe for prevention of the capacity decrease
according to the ambient air conditions and the dewing on the pipe
surface by the low pressure.
Check to ensure that there is no gas leakage. When large amount of
the refrigerant leaks, the troubles as follows may occurs.
1. Oxygen Deficiency
2. Generation of Harmful Gas due to chemical reaction with fire.
REFRIGERANT PIPING & REFRIGERANT CHARGE
PMML0354A rev.1 - 03/2015
12
