Leak Test And Vacuum Drying; Pipe Insulation; Additional Refrigerant Charge - Panasonic CU-5MX1SPP Manual De Instalación

Leak test and vacuum drying

The units were checked for leaks by the manufacturer.
Confirm that the valves are firmly closed before pressure test or
vacuuming.
Air tight test and vacuum drying
Air tight test: Make sure to use nitrogen gas.
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Pressurize the liquid and gas pipes to 3.2 MPa (do not pressurize
more than 3.2 MPa). If the pressure does not drop within 24 hours,
the system passes the test. If the pressure drops, check where the
nitrogen leaks from.
Vacuum drying: Use a vacuum pump which can evacuate to
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-100.7 kPa (5 Torr, -755 mmHg).
1. Evacuate the system from the liquid and gas pipes by using a
vacuum pump for more than 2 hours and bring the system to
-100.7 kPa. After keeping the system under that condition for more
than 1 hour, check if the vacuum gauge rises or not. If it rises, the
system may either contain moisture inside or have leaks.
Following should be executed if there is a possibility of moisture
2.
remaining inside the pipe (if piping work is carried out during the
raining season or over a long period of time rainwater may enter the
pipe during work).
After evacuating the system for 2 hours, pressurize the system to
0.05 MPa (vacuum break) with nitrogen gas and evacuate the
system again using the vacuum pump for 1 hour to -100.7 kPa
(vacuum drying). If the system cannot be evacuated to -100.7 kPa
within 2 hours, repeat the operation of vacuum break and vacuum
drying.
Then, after leaving the system in vacuum for 1 hour, confirm that the
vacuum gauge does not rise.

Pipe insulation

After finishing the leak test and vacuum drying, the piping must be
insulated. Take into account the following points:
Make sure to insulate the connection piping and refrigerant
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branch kits entirely.
Make sure to insulate the gas side connection piping and
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refrigerant branch kits entirely against heat, and depending on
operation conditions (e.g. when performing cooling operation
with an outside air temperature of ≤15°C), consider to also make
a heat insulation of the liquid side connection piping and
refrigerant branch kits to prevent dewing.
Use heat resistant polyethylene foam which can withstand a
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temperature of 70°C for liquid side piping and polyethylene foam
which can withstand a temperature of 120°C for gas side piping.

Additional refrigerant charge

Refrigerant may only be charged after performing the leak
test and the vacuum drying (see above).
When charging a system, care shall be taken that its
maximum permissible charge is never exceeded, in view of
the danger of liquid hammer.
Charging with an unsuitable substance may cause
explosions and accidents, so always ensure that the
appropriate refrigerant (R-407C) is charged.
Refrigerant containers shall be opened slowly.
Always use protective gloves and protect your eyes when
charging refrigerant.
I This outdoor unit is factory charged with refrigerant and
depending on pipe sizes and pipe lengths some systems require
additional charging of refrigerant.
Charge the refrigerant to the liquid pipe in its liquid state. Since
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R-407C is a mixed refrigerant, its composition changes if
charged in a state of gas and normal system operation would no
longer be assured.
CU-5~10MX1SPP
Urban Multi air conditioner
4PW12336-1C
Determine the weight of refrigerant to be charged additionally
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referring to the item "Additional refrigerant charge" in "Example
of connection" on page 6. And fill in the amount in the 'Request
for the indication of additional refrigerant charging amount and
installation date' attached to the unit.
After the vacuum drying is finished, charge the additional
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refrigerant in its liquid state through the liquid stop valve service
port taking into account following instructions:
- Check that gas and liquid stop valves are closed.
- Stop the compressor and charge the specified weight of
refrigerant.
If the outdoor unit is not in operation and the total amount cannot
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be charged, follow the procedures for additional refrigerant
charge shown below.
Make sure to use installation tools you exclusively use on
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R-407C installations to withstand the pressure and to prevent
foreign materials from mixing into the system.
NOTE Procedures for charging additional refrigerant
Refer to figure 2.
R-407C refrigerant cylinder
1
vacuum pump
2
liquid stop valve with service port
3
gas stop valve with service port
4
valve A
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1 Fully open the gas stop valve. The liquid stop
valve and "valve A" shown below must be kept
closed. Start the additional refrigerant charging
operation.
Stop the additional refrigerant charging operation
2
when the specified amount is charged.
3 Fully close the liquid side stop valve. For setting
the additional refrigerant charging operation, see
the "Caution on operation" label on the rear of the
front panel (left) of the outdoor unit.
1 If the refrigerant cylinder is siphonal, set it upright
while charging additional refrigerant.
2 Be sure to size up the main gas line in the connection
piping of the suction gas piping if the equivalent length
of pipping between indoor units and outdoor unit
exceeds 90m in order to minimize the reduction of
capacity.
CU-5MX1..............................ø19.1 © ø22.2
CU-8MX1..............................- - -
CU-10MX1............................ø28.6 © ø31.8
3 If the refrigerant pipe is longer than specified, be sure
to add refrigerant. (Incorrect amount of refrigerant
may cause the compressor to malfunction.)
Installation manual
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