Mitsubishi Electric PEAD-M140JA Installation Manual Download Page 15

Page: 15 / 176

6. Refrigerant piping work

6.4. Purging procedures leak test

6.5. Drain piping work

• Ensure that the drain piping is downward (pitch of more than 1/100) to the outdoor

(discharge) side. Do not provide any trap or irregularity on the way.

• Ensure that any cross-wise drain piping is less than 20 m (excluding the difference

of elevation). If the drain piping is long, provide metal braces to prevent it from
waving. Never provide any air vent pipe. Otherwise drain may be ejected.

• Use a hard vinyl chloride pipe VP-25 (with an external diameter of 32 mm) for drain

piping.

• Ensure that collected pipes are 10 cm lower than the unit body’s drain port.
• Do not provide any odor trap at the drain discharge port.
• Put the end of the drain piping in a position where no odor is generated.
• Do not put the end of the drain piping in any drain where ionic gases are generated.

[Fig. 6-5-1] (P.5)

Grouped piping

PEAD-M·JA model

[PEAD-M·JA model]
1. Insert the drain hose (accessory) into the drain port (insertion margin: 25 mm).

(The drain hose must not be bent more than 45° to prevent the hose from
breaking or clogging.)
(Attach the hose with glue, and fix it with the band (small, accessory).)

2. Attach the drain pipe (O.D. ø32 PVC TUBE PV-25, field supply).

(Attach the pipe with glue, and fix it with the band (small, accessory).)

3. Perform insulation work on the drain pipe (O.D. ø32 PVC TUBE PV-25) and on the

socket (including elbow).

4. Check the drainage. (Refer to [Fig. 6-6])
5. Attach the insulating material (accessory), and fix it with the band (large,

accessory) to insulate the drain port.

[Fig. 6-5-2] (P.5) *only on the PEAD-M·JA model

[PEAD-M·JA model]
1. Insert the drain hose (accessory) into the drain port.

(The drain hose must not be bent more than 45° to prevent the hose from
breaking or clogging.)
The connecting part between the indoor unit and the drain hose may be
disconnected at the maintenance. Fix the part with the accessory band, not be
adhered.

2. Attach the drain pipe (O.D. ø32 PVC TUBE, field supply).

(Attach the pipe with glue for the hard vinyl chloride pipe, and fix it with the band
(small, accessory).)

3. Perform insulation work on the drain pipe (O.D. ø32 PVC TUBE) and on the

socket (including elbow).

[Fig. 6-5-3] (P.5) *only on the PEAD-M·JA model

PURGING PROCEDURES

Connect the refrigerant pipes (both the liquid and gas pipes) between the indoor
and the outdoor units.

Remove the service port cap of the stop valve on the side of the outdoor unit gas pipe.
(The stop valve will not work in its initial state fresh out of the factory (totally closed
with cap on).)

Connect the gage manifold valve and the vacuum pump to the service port of the
stop valve on the gas pipe side of the outdoor unit.

Run the vacuum pump. (Vacuumize for more than 15 minutes.)

Check the vacuum with the gage manifold valve, then close the gage manifold
valve, and stop the vacuum pump.

Leave it as is for one or two minutes. Make sure the pointer of the gage manifold
valve remains in the same position. Confirm that the pressure gage show -0.101MPa
(-760 mmHg).

*4 to 5 turns

Remove the gage manifold valve quickly from the service port of the stop valve.

After refrigerant pipes are connected and evacuated, fully open all stop valves on
gas and liquid pipe sides.
Operating without fully opening lowers the performance and causes trouble.

Pipe length :

7 m maximum

No gas charge is needed.

Pipe length exceeding 7 m

Charge the prescribed

amount of gas.

Hexagonal wrench

*Open

*Close

Stop valve

Service port

Stop
valve