Sealing Test; Vacuum Process; Additional Charging - Rheem RHMV4821SNACJA Manual De Instalación

3.9. Sealing test

• Before operating the compressor, install the pipes and securely connect them.
Otherwise, if the pipes are not installed and if the valves are open when the
compressor operates, air could enter the refrigeration cycle. If this happens, the
pressure in the refrigeration cycle will become abnormally high and cause damage
or injury.
• After the installation, make sure there is no refrigerant leakage. If the refrigerant
leaks into the room and becomes exposed to a source of fi re such as a fan heater,
stove, or burner, it produces a toxic gas.
• Use only nitrogen gas.
Never use refrigerant gas, oxygen, fl ammable gas or poisonous gas to pressurize
the system. (If oxygen is used. There is danger of an explosion.)
• Do not shock during sealing test.
It can rupture the pipes and cause serious injury.
• Do not turn on the power unless all operations are complete.
• Do not block the walls and the ceiling until the sealing test and charging of the
refrigerant gas have been completed.
After connecting the pipes, perform a sealing test.
Recheck that the spindle of the 3-way valve are closed before performing a sealing test.
Charging
port
Blank cap
Hexagon wrench 4 mm
Pour nitrogen gas through both the liquid pipe and the gas pipe.
Pressurize nitrogen gas to 609 psi (4.2 MPa) to perform the sealing test.
Check all flare connection and brazed areas.
Then, check that the pressure has not decreased.
Compare the pressures after pressurizing and letting it stand for 24 hours, and check that
the pressure did not decreased.
* When the outdoor temperature changes 9 degrees F (5 degrees C), the test pressure
changes 7.25 psi (0.05 MPa.).
If the pressure has dropped, the pipe joints may be leaking.
If a leakage is found, immediately repair it and perform a sealing test again.
* Decrease the pressure of nitrogen gas before brazing.
After completing the sealing test, release the nitrogen gas from both valves.
Release the nitrogen gas slowly.

3.10. Vacuum process

• Do not turn on the power unless all operations are complete.
• If the system is not evacuated suffi ciently, its performance will drop.
• Be sure to evacuate the refrigerant system using a vacuum pump.
• The refrigerant pressure may sometimes not rise when a closed valve is opened
after the system is evacuated using a vacuum pump. This is caused by the closure
of the refrigerant system of the outdoor unit by the electronic expansion valve. This
will not affect the operation of the unit.
• Use a clean gauge manifold and charging hose that were designed specifi cally for
use with R410A. Using the same vacuum equipment for different refrigerants may
damage the vacuum pump or the unit.
• Do not purge the air with refrigerants, but use a vacuum pump to evacuate the
system.
- If moisture enter the piping, follow below. (i.e., if doing work during the rainy
season, if the actual work takes long enough that condensation may form on the
inside of the pipes, if rain might enter the pipes during work, etc.)
- After operating the vacuum pump for 2 hours, pressurize to 7.25 psi (0.05 MPa)
(i.e., vacuum breakdown) with nitrogen gas, then depressurize down to 500 mi-
crons (-100.7 kPa) for an hour using the vacuum pump (vacuum process).
- If the pressure does not reach 500 microns (-100.7 kPa) even after depressurizing
for at least 2 hours, repeat the vacuum breakdown - vacuum process perform
triple evacuation procedure as necessary to bring the vacuum down to 500 mi-
crons (-100.7 kPa) or lower.
• After vacuum process, maintain the vacuum for an hour and make sure the pressure
does not rise by monitoring with a vacuum gauge.
En-8
9374995677-02_IM.indb 8 9374995677-02_IM.indb 8
WARNING
CAUTION
Service hose
with valve core
Charging
port cap
3-way
valve
Connecting
pipe
CAUTION
Evacuation procedure
(1) Remove the caps of the gas pipe and liquid pipe and check that the valves are
closed.
(2) Remove the charging cap.
(3) Connect a vacuum pump and a pressure gauge to a charging hose and connect it to
the charging port.
(4) Activate the vacuum pump and vacuum the indoor unit and connection piping until
the pressure gauge becomes 500 microns (-100.7 kPa).
Evacuate from both the gas pipe and the liquid pipe.
(5) Continue evacuating the system for 1 hour after the pressure gauge reads
500 microns (-100.7 kPa).
(6) Remove the charging hose and reinstall the charging cap.
1/4 (6.35)
3/8 (9.52)
Blank cap
1/2 (12.70)
[in (mm)]
5/8 (15.88)
3/4 (19.05)
Charging port cap
Pressure
Outdoor unit
gauge
Indoor
unit

3.11. Additional charging

WARNING
When moving and installing the air conditioner, do not mix gas other than the specifi ed
refrigerant R410A inside the refrigerant cycle.
If air or other gas enters the refrigerant cycle, the pressure inside the cycle will rise to
an abnormally high value and cause breakage, injury, etc.
CAUTION
• Do not turn on the power unless all operations are complete.
• After vacuuming the system, add refrigerant.
• Do not charge the system with a refrigerant other than R410A.
• Always keep to the limit on the total amount of refrigerant. Exceeding the limit on the
total amount of refrigerant will lead to malfunction during charging of refrigerant.
• Do not reuse recovered refrigerant.
• When charging the refrigerant R410A, always use an electronic scales for refrigerant
charging (to measure the refrigerant by weight). Adding more refrigerant than the
specifi ed amount will cause a malfunction.
• When charging the refrigerant, take into account the slight change in the composition
of the gas and liquid phases, and always charge from the liquid phase side
whose composition is stable. Adding refrigerant through the gas pipe will cause a
malfunction.
• Add refrigerant by charging the system with the refrigerant in the liquid state. If the
refrigerant cylinder is equipped with a siphon, it is not necessary to place the cylinder
upright.
• Check if the steel cylinder has a siphon installed or not before fi lling. (There is an
indication "with siphon for fi lling liquid" on the steel cylinder.)
Filling method for cylinder with siphon
R410A
Set the cylinder vertical and fi ll with the liquid.
Gas
(Liquid can be fi lled without turning bottom up with the
siphon inside.)
Liquid
Filling method for other cylinders
R410A
Turn bottom up and fi ll with liquid.
Gas
(Be careful to avoid turning over the cylinder.)
Liquid
• Be sure to use the special tools for R410A for pressure resistance and to avoid
mixing of impure substances.
• If the units are further apart than the maximum pipe length, correct operation can not
be guaranteed.
• Make sure to back closing valve after refrigerant charging. Otherwise, the
compressor may fail.
• Minimize refrigerant release to the air. Excessive release is prohibited under the
Freon Collection and Destruction Law.
Tightening torque [lbs·ft (N·m)]
11.8 to 13.3 (16 to 18)
23.6 to 31.0 (32 to 42)
36.1 to 45.0 (49 to 61)
46.5 to 55.3 (63 to 75)
66.4 to 81.1 (90 to 110)
9.2 to 11.8 (13 to 16)
Pressure regu-
lating valve
Nitrogen
Vacuum
Scale
pump
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