Mitsubishi Electric Mr.Slim MXZ-2A20NA, Installation Manual

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5
CONNECTING WIRES
• Wire to be AWG22 double insulated, 300 V insulation. Equal to Belden 9407 (for 12-24 V DC).
• Use copper conductors only.
Note:
*1 Wire to be AWG22 double insulated, 300 V insulation. Equal to Belden 9407.
*2 Power supply cable and grounding wire must use copper wire AWG14.
*3 Connect grounding wire with grounding terminal by using a ring tongue solderless terminal.
WARNING:
Use the indoor/outdoor unit connecting wire that meets the Standards to connect the indoor and outdoor
units and fix the wire to the terminal block securely so that no external force is conveyed to the connect-
ing section of the terminal block. An incomplete connection or fixing of the wire could result in a fire.
1
Remove the service panel.
2
Fix the conduit connector to conduit cover with
lock nut then secure it against unit with screws.
3
Fix the conduit cover to the outdoor unit then
secure it with screws.
4
Connect power supply and indoor/outdoor con-
necting wire to the terminal block.
(Leave some slack in wires to allow easier serv-
icing.)
CAUTION:
Use care so as connecting wires do not con-
tact pipes.
WARNING:
•••••
Be sure to attach the service panel of the outdoor unit securely, otherwise it may result in a fire or an
electric shock from dust or water.
•••••
Use the indoor/outdoor unit connecting wire that meets the Standards to connect the indoor and outdoor
units and fix the wire to the terminal block securely so that no external force is conveyed to the connect-
ing section of the terminal block. Incomplete connection or fixing of the wire could result in a fire.
•••••
Be sure to attach the terminal block cover on the both indoor and outdoor units. If the terminal block
cover is incorrectly attached, it may cause a risk of fire or electric shock due to dust or water penetration.
5. INDOOR/OUTDOOR UNITS CONNECTION FINISHING AND
TEST RUN
5-1 TOOLS DEDICATED FOR THE AIR CONDITIONER WITH R410A
REFRIGERANT
The following tools are required for R410A refrigerant. Some R22 tools can be substituted for R410A tools.
R410A tools Can R22 tools be used? Description
Gauge manifold No R410A has high pressures beyond the measurement range of existing gauges.
Charge hose No
Hose material and cap size have been changed to improve the pressure resist-
ance.
Gas leak detector No Dedicated for HFC refrigerant.
Torque wrench
Yes 1/4 and 3/8
No 1/2
Flare tool Yes Clamp bar hole has been enlarged to reinforce the spring strength in the tool.
Flare gauge New Provided for flaring work (to be used with R22 flare tool).
New
Provided to prevent the back flow of oil. This adapter enables you to use exist-
ing vacuum pumps.
New
It is difficult to measure R410A with a charging cylinder because the refrigerant
bubbles due to high pressure and high-speed vaporization.
No: Not substitutable for R410A Yes: Substitutable for R410A
5-2 FLARED CONNECTIONS
PIPE LENGTH AND HEIGHT DIFFERENCE
Limits 2A20NA
Pipe length per indoor unit 25 m (82 ft.) max.
Total pipe length for multi-system 50 m (164 ft.) max.
Height difference 10 m (33 ft.) max.
No. of bends per indoor unit 25 max.
Total No. of bends for multi-system 50 max.
Refrigerant adjustment ....... If pipe length exceeds 40 m (131 ft.), additional refrigerant (R410A) charge is re-
quired.
(The outdoor unit is charged with refrigerant for total pipe length up to 40 m (131 ft.).)
Pipe length
Up to 40 m (131 ft.) No additional charge is required.
Exceeding 40 m (131 ft.)
Additional charge is required.
(Refer to the table below.)
Refrigerant to be added 1.06 oz each 5 ft.
• For pipe size, see the table below.
Lock nut Connector
Grounding terminal
Electronic scale for
refrigerant charging
Vacuum pump
adaptor
Outdoor
unit
Indoor unit
ı
UNIT
Indoor unit
Å
UNIT
L2 L1
S1S2S3
S2S3 S1
S1S2S3
S2S3 S1
Remark:
* A disconnect switch may be required. Check the
local code.
** Use a ring tongue terminal in order to connect a
ground wire to terminal.
INDOOR UNIT
Å
Terminal block
INDOOR UNIT
ı
Terminal block
Grounding
terminal ** Grounding
terminal **
Disconnect switch *
Disconnect switch *
208/230V AC
1phase 60Hz
208/230V AC
1phase 60Hz
DC12-24 V
(Polar)
DC12-24 V
(Polar)
Grounding
terminal ** Grounding
terminal **
Ground
Power supply 208/230V AC
1phase 2wires 60Hz.
OUTDOOR UNIT
Terminal block
UNIT
Å
Terminal block
UNIT
ı
Connect wires to the matching numbers of terminals.
Conduit
cover