Mitsubishi Electric MFZ-KA25VA Manuel D'installation page 10

5-3 PIPE CONNECTION
Note:
Fasten a flare nut with a torque wrench as specified in the table below.
When fastened too tight, a flare nut may broken after a long period and cause a leakage of refrigerant.
1. Indoor unit connection
Connect both liquid and gas pipings to indoor unit.
• Apply a thin coat of refrigeration oil J on the seat surface of pipe.
• For connection first align the center, then tighten the first 3 to 4 turns of flare nut.
• Use tightening torque table below as a guideline for indoor unit side union joint section, and tighten using
two wrenches. Excessive tightening damages the flare section.
Pipe diameter Tightening torque
mm N·m kgf·cm
ø6.35 13.7 to 17.7 140 to 180
ø9.52 34.3 to 41.2 350 to 420
ø12.7 49.0 to 56.4 500 to 575
2. Outdoor unit connection
Connect pipes to stop valve pipe joint of the outdoor unit in the same manner applied for indoor unit.
• For tightening, use a torque wrench or spanner and use the same tightening torque applied for indoor
unit.
INSULATION AND TAPING
1 Cover piping joints with pipe cover.
2 For outdoor unit side, surely insulate every piping including valves.
3 Using piping tape G, apply taping starting from the entry of outdoor unit.
• Stop the end of piping tape G with tape (with adhesive agent attached).
• When piping have to be arranged through above ceiling, closet or where the temperature and humidity
are high, wind additional commercially sold insulation for prevention of condensation.
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5-4 TEST RUN
• Before performing the test run, recheck for any wrong wiring.
Wrong wiring prevents normal operation or results in blown fuse disabling operation.
• The test run can be started by pressing EMERGENCY OPERATION switch. When the EMERGENCY OP-
ERATION switch is once pressed, the unit will start the test run (continuous operation) for 30 minutes.
A thermostat does not work during this time. After 30 minutes the unit will start the EMERGENCY OPERA-
TION at a fixed temperature setting of 24 °C in COOL MODE.
• Perform test run in the following procedure.
• Press the EMERGENCY OPERATION switch.
Note:
Three seconds after the EMERGENCY OPERATION switch is pressed, the auto front panel starts moving
forward. Close the front panel before it starts moving.
1 Press it once, and after test run for 30 minutes the EMERGENCY COOL MODE starts.
If the left side lamp of the operation indicator blinks every 0.5 seconds, inspect the indoor/outdoor unit
connecting wire A for mis-wiring.
2 Press it once more, and the EMERGENCY HEAT MODE starts.
3 Press it once more, and the operation stops.
(The operation mode changes in order of 1 ~ 3 every time the EMERGENCY OPERATION switch is
pressed.)
Note:
In starting the heating operation, indoor unit fan may not operate to prevent blowing cool air. Please wait for a
few minutes until the temperature of heat exchanger rises and warm air blows out.
Checking the remote (infrared) signal reception
Press the ON/OFF button on the remote controller and check that an electronic sound is heard from the indoor
unit. Press the ON/OFF button again to turn the air conditioner off.
If the indoor unit is operated with the remote controller, both the test run and the emergency operation are
released by commands from the remote controller.
•
Once the compressor stops, the restart preventive device operates so the compressor will not operate for
three minutes to protect the air conditioner.
10
EMERGENCY
E.O.
OPERATION switch
SW
(E.O. SW)