Drain Piping Work; Connecting Electrical Connections; Electrical Wiring - Mitsubishi Electric CITY MULTI PWFY-P100VM-E-BU Manuel D'installation

Caution:
• Install the refrigerant piping for the indoor unit in accordance with the fol-
lowing.
1. Cut the tip of the indoor unit piping, remove the gas, and then remove the brazed
cap.
[Fig. 9.1.1] (P.3)
A Cut here
B Remove brazed cap
2. Pull out the thermal insulation on the site refrigerant piping, braze the unit piping,
and replace the insulation in its original position.
Wrap the piping with insulating tape.
Note:
• Pay strict attention when wrapping the copper piping since wrapping the
piping may cause condensation instead of preventing it.
* Before brazing the refrigerant piping, always wrap the piping on the main body,
and the thermal insulation piping, with damp cloths to prevent heat shrink-
age and burning the thermal insulation tubing. Take care to ensure that the
flame does not come into contact with the main body itself.
[Fig. 9.1.2] (P.3)
A Thermal insulation
C Wrap with damp cloth
E Ensure that there is no gap here
Cautions On Refrigerant Piping
 Be sure to use non-oxidative brazing for brazing to ensure that no foreign
matter or moisture enter into the pipe.
 Be sure to apply refrigerating machine oil over the flare connection seating
surface and tighten the connection using a double spanner.
 Provide a metal brace to support the refrigerant pipe so that no load is
imparted to the indoor unit end pipe. This metal brace should be provided
50 cm away from the indoor unit's flare connection.
Warning:
• Do not use refrigerant other than the type indicated in the manuals provided
with the unit and on the nameplate.
- Doing so may cause the unit or pipes to burst, or result in explosion or fire during
use, during repair, or at the time of disposal of the unit.
- It may also be in violation of applicable laws.
- MITSUBISHI ELECTRIC CORPORATION cannot be held responsible for mal-
functions or accidents resulting from the use of the wrong type of refrigerant.
• When installing and moving the unit, do not charge it with refrigerant other
than the refrigerant (R407C or R22) specified on the unit.
- Mixing of a different refrigerant, air, etc. may cause the refrigerant cycle to mal-
function and result in severe damage.
Caution:
• Use refrigerant piping made of C1220 (CU-DHP) phosphorus deoxidized
copper as specified in the JIS H3300 "Copper and copper alloy seamless
pipes and tubes". In addition, be sure that the inner and outer surfaces of
the pipes are clean and free of hazardous sulphur, oxides, dust/dirt, shaving
particles, oils, moisture, or any other contaminant.
• Never use existing refrigerant piping.
- The large amount of chlorine in conventional refrigerant and refrigerator oil in
the existing piping will cause the new refrigerant to deteriorate.
• Store the piping to be used during installation indoors and keep both ends
of the piping sealed until just before brazing.
- If dust, dirt, or water gets into the refrigerant cycle, the oil will deteriorate and the
compressor may fail.

10. Electrical wiring

Precautions on electrical wiring
Warning:
Electrical work should be done by qualified electrical engineers in accordance
with "Engineering Standards For Electrical Installation" and supplied installa-
tion manuals. Special circuits should also be used. If the power circuit lacks
capacity or has an installation failure, it may cause a risk of electric shock or
fire.
1. Be sure to take power from the special branch circuit.
2. Be sure to install an earth leakage breaker to the power.
3. Install the unit to prevent that any of the control circuit cables (remote controller,
transmission cables, or external input/output line) is brought in direct contact with
the power cable outside the unit.
4. Ensure that there is no slack on all wire connections.
5. Some cables (power, remote controller, transmission cables, or external input/out-
put line) above the ceiling may be bitten by mouses. Use as many metal pipes as
possible to insert the cables into them for protection.
10
B Pull out insulation
D Return to original position
F Wrap with insulating tape

9.2. Drain piping work

1. 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. (1)
2. 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.
3. Use a hard vinyl chloride pipe VP-25 (with an external diameter of 32 mm) for
drain piping.
4. Ensure that collected pipes are 10 cm lower than the unit body's drain port as
shown in 2.
5. Do not provide any odor trap at the drain discharge port.
6. Put the end of the drain piping in a position where no odor is generated.
7. Do not put the end of the drain piping in any drain where ionic gases are gener-
ated.
[Fig. 9.2.1] (P. 3)
A Downward slope 1/100 or more
B Drain hose
C Unit
D Collective piping
E Maximize this length to approx. 10 cm

9.3. Connecting electrical connections

Verify that the model name on the operating instructions on the cover of the control
box is the same as the model name on the nameplate.
Step 1
Remove the screws holding the terminal box cover in place.
[Fig. 9.3.1] (P. 3)
A Screws
C Control box
Note:
Ensure that the wiring is not pinched when fitting the terminal box cover.
Pinching the wiring may cut it.
Caution:
Install wiring so that it is not tight and under tension. Wiring under tension
may break, or overheat and burn.
• Fix power source external input/output line wiring to control box by using buffer
bushing for tensile force to prevent electric shock. (PG connection or the like.)
Connect transmission wiring to transmission terminal block through the knockout
hole of control box using ordinary bushing.
• After wiring is complete, make sure again that there is no slack on the connec-
tions, and attach the cover onto the control box in the reverse order removal.
[Fig. 9.3.2] (P. 3)
A To prevent external tensile force from applying to the wiring connection section of
power source terminal block use buffer bushing like PG connection or the like.
B External signal input cable
C External signal output cable
D Power source wiring
E Tensile force
F Use ordinary bushing
G Transmission cable and MA remote controller cable
Caution:
Wire the power supply so that no tension is imparted. Otherwise disconnec-
tion, heating or fire result.
6. Never connect the power cable to leads for the transmission cables. Otherwise
the cables would be broken.
7. Be sure to connect control cables to the indoor unit, remote controller, and the out-
door unit.
8. Be sure to ground the unit.
9. Select control cables from the conditions given in page 11.
Caution:
Be sure to put the unit to the ground on the outdoor unit side. Do not connect
the earth cable to any gas pipe, water pipe, lightening rod, or telephone earth
cable. Incomplete grounding may cause a risk of electric shock.
Types of control cables
1. Wiring transmission cables
• Types of transmission cables
Design wiring in accordance with the following table <Table 1>.
• Be sure to use cables supplied with supplementary insulation.
B Front panel