Daikin RX5MY1 Installation Manual Download

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English

Not recommendable but in case of emergency

You must use a torque wrench but if you are obliged to install the unit without
a torque wrench, you may follow the installation method mentioned below.

After the work is finished, make sure to check that there is no gas leak.

When you keep on tightening the flare nut with a spanner, there is a
point where the tightening torque suddenly increases. From that
position, further tighten the flare nut the angle shown below:

Disposal requirements

Dismantling of the unit, treatment of the refrigerant, oil and eventual
other parts, should be done in accordance with the relevant local and
national regulations.

6-5 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
branch kits entirely.

•

Be sure to insulate the liquid-side and gas-side piping for the
inter-unit piping and the refrigerant branch kits and always use
RX18-type or better insulation for the oil pressure equalizer.
Not insulating them may cause leaking. (The gas piping can reach
temperatures of 120°C. Be sure the insulation used can withstand
such temperatures.)

•

If you think the humidity around the cooling piping might exceed
30°C and RH80%, reinforce the insulation on the cooling piping
(at least 20mm thick). Condensation might form on the surface of
the insulation.

•

If there is a possibility that condensation on the shut-off valve
might drip down into the indoor unit through gaps in the insulation
and piping because the outdoor unit is located higher than the
indoor unit, etc., this must be prevented by corking the connec-
tions, etc.

(Refer to figure 11)

One outdoor unit installed:

Liquid line shutoff valve

Gas line shutoff valve

Outer-to-inner interconnecting piping

Calking treatment, etc.

Heat insulator

Oil-equalizing line shutoff valve

When multiple outdoor units installed:

Caution

Be sure to insulate local pipes, as touching them can cause
burns.

6-6 Additional refrigerant charge

Caution

Refrigerant cannot be charged until field wiring has been completed.
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
(R22) is charged.
Refrigerant containers shall be opened slowly.
Always use protective gloves and protect your eyes when charg-
ing refrigerant.

TO AVOID COMPRESSOR BREAKDOWN. DO NOT CHARGE THE
REFRIGERANT MORE THAN THE SPECIFED AMOUNT TO RAISE
THE CONDENSING PRESSURE.

•

This outdoor unit is factory charged with refrigerant and depend-
ing on pipe sizes and pipe lengths some systems require addi-
tional charging of refrigerant.

•

Determine the amount of refrigerant to be added by referring to
the table, write it down on the included “Added Refrigerant” plate
and attach it to the rear side of the front cover.
Note: refer to the example of connection for the amount to be
added.

•

After the vacuum drying is finished, charge the additional refriger-
ant 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 refrig-
erant.

•

If the outdoor unit is not in operation and the total amount cannot
be charged, follow the procedures for additional refrigerant
charge shown below.

•

Make sure to use installation tools you exclusively use on R22
installations to withstand the pressure and to prevent foreign
materials from mixing into the system.

Note

•

Procedures for charging additional refrigerant.

One outdoor unit installed: In case of RX5-16 type

(Refer to figure 12)

Pressure reducing valve

Nitrogen

Tank

Siphon system

Measuring instrument

Vacuum pump

Valve A

Gas side

Outdoor unit

10.

Liquid side

11.

Indoor unit

12.

Shutoff valve service port

13.

Charge hose

14.

To indoor unit

15.

Oil-equalizing line

16.

Valve B

17.

Dotted lines represent onsite piping

[Additional refrigerant charge procedure]
To learn the system settings for additional refrigerant charging, refer
to the [Service Precaution] label attached on the back of the electric
box lid in the outdoor unit.

Fully open the gas line shutoff valve (liquid line shutoff valve
and valve A above must be left fully closed) and start the addi-
tional refrigerant charge operation.

After the system is charged with a specified amount of refrig-
erant, press the confirmation button (BS3) on the P-board
(A1P) in the outdoor unit to stop the additional refrigerant
charge operation.

Immediately restore the shutoff valve to the following status.
(The test run cannot be performed properly if the shut-off valve
is not correct.)

When multiple outdoor units installed: In case of
RX18-48MY1(E)
(Refer to figure 12)

Fully open the gas line shutoff valve/oil-equalizing line shutoff
valve (liquid line shutoff valve and valves A and B above must be
left fully closed), start the additional refrigerant charge operation.

After the system is charged with a specified amount of refrig-
erant, press the confirmation button (BS3) on the P-board
(A1P) in the outdoor unit to stop the additional refrigerant
charge operation.

Immediately restore the shutoff valve to the following status.
(The test run cannot be performed properly if the shut-off valve
is not correct.)

Caution

If the refrigerant cylinder is siphonal, set it upright while charging
additional refrigerant.

Pipe size

Further tightening angle

Recommended arm length of tool

9.5 (3/8”)

60 to 90 degrees

Approx. 200 mm

12.7 (1/2”)

30 to 60 degrees

Approx. 250 mm