Mitsubishi Electric MFZ-KT25VG Installation Manual Download Page 9

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EN-8

3-1. FLARING WORK

1) Cut the copper pipe correctly with pipe cutter. (Fig. 1, 2)

2) Completely remove all burrs from the cut cross section of pipe. (Fig. 3)

• Put the end of the copper pipe to downward direction as you remove burrs in order

to avoid to let burrs drop in the piping.

3) Remove flare nuts attached to indoor and outdoor units, then put them on pipe having

completed burr removal. (Not possible to put them on after flaring work.)

4) Flaring work (Fig. 4, 5). Firmly hold copper pipe in the dimension shown in the table.

Select A mm from the table according to the tool you use.

5) Check

• Compare the flared work with Fig. 6.

• If flare is noted to be defective, cut off the flared section and do flaring work again.

3-2. PIPE CONNECTION

• Fasten flare nut with a torque wrench as specified in the table.

• When fastened too tight, flare nut may break after a long period and cause refrigerant

leakage.

• Be sure to wrap insulation around the piping. Direct contact with the bare piping may

result in burns or frostbite.

Indoor unit connection

Connect both liquid and gas pipings to indoor unit.

• Apply a thin coat of refrigeration oil (K) on the flared ends of the pipes. Do not apply

refrigeration oil on screw threads. Excessive tightening torque will result in damage

on the screw.

• For connection, first align the center, then tighten the first 3 to 4 turns of flare nut, by

hand.

• Use tightening torque table above as a guideline for indoor unit side union joint section,

and tighten using two wrenches. Excessive tightening damages the flare section.

Copper

pipe

Good

Tilted Uneven Burred

No good

Fig. 1

Fig. 2

Burr

Copper pipe

Spare reamer

Pipe cutter

Clutch type

Flaring tool

Fig. 4

Fig. 3

Smooth all

around

Even length

all around

Inside is shining

without any

scratches.

Flare nut

Die

Fig. 5

Fig. 6

Copper

pipe

Wing nut type

WARNING

When installing the unit, securely

connect the refrigerant pipes be-

fore starting the compressor.

3. FLARE CONNECTION, PIPE CONNECTION

4-3. EXPLANATION TO THE USER

• Using the OPERATING INSTRUCTIONS, explain to the user how to use the air conditioner (how to use the remote controller, how to remove the air filters, how to

remove or put the remote controller in the remote controller holder, how to clean, precautions for operation, etc.)

• Recommend the user to read the OPERATING INSTRUCTIONS carefully.

Caution:

• After test run or remote signal reception check, turn off the unit with the E.O. SW or the remote controller before turning off the power supply. Not doing so will

cause the unit to start operation automatically when power supply is resumed.

To the user

• After installing the unit, make sure to explain the user about auto restart function.

• If auto restart function is unnecessary, it can be deactivated. Consult the service representative to deactivate the function. Refer to the service manual for details.

4-2. AUTO RESTART FUNCTION

This product is equipped with an auto restart function. When the power supply is stopped during operation, such as during blackouts, the function automatically

starts operation in the previous setting once the power supply is resumed. (Refer to the operating instructions for details.)

4-1. TEST RUN

Make sure the following is done.

• Panel is installed correctly.

• Indoor and outdoor units are installed correctly, and power is supplied.
1) Press the E.O. SW once for

COOL

, and twice for

HEAT

operation. Test run will be performed for 30 minutes. If the left lamp of the opera

tion indicator blinks every 0.5 seconds, inspect the indoor/outdoor unit connecting wire (A) for mis-wiring. After the test run, emergency

mode (set temperature 24ºC) will start.

2) To stop operation, press the E.O. SW several times until all LED lamps turn off. Refer to operating instructions for details.