Refrigerant Pipe And Drain Pipe Specifications; Refrigerant Pipe, Drain Pipe And Filling Port; Connecting Refrigerant Pipes And Drain Pipes; Refrigerant Piping Work - Mitsubishi Electric CITY MULTI PWFY-P100VM-E-BU Manuel D'utilisation

Conditions
(1) When Y, Zubadan, WY, or Replace-Y series models are used for the outdoor
units
(2) When PWFY-P140VM-E1-AU units are used for heating only and are placed on
the same refrigerant circuit as the indoor units or other
PWFY-P140VM-E1-AU units
However, this does not apply in cases where brine is added to the water line or
cases where the unit is run in heating mode only as a refrigerant circuit system
Set Dip SW3-6 to ON. Make sure the version of the software is 1.18 or later.

8. Refrigerant pipe and drain pipe specifications

To avoid dew drops, provide sufficient antisweating and insulating work to the refrig-
erant and drain pipes.
When using commercially available refrigerant pipes, be sure to wind commercially
available insulating material (with a heat-resisting temperature of more than 100 ˚C
1 Select the thickness of insulating material by pipe size.
Model
Gas
Liquid
Drain
Insulating material's thickness
2 If the unit is used on the highest story of a building and under conditions of high
temperature and humidity, it is necessary to use pipe size and insulating mate-
rial's thickness more than those given in the table above.

8.1. Refrigerant pipe, drain pipe and filling port

[Fig. 8.1.1] (P.5)
A Refrigerant piping (gas)
C Water inlet
E Drain outlet

9. Connecting refrigerant pipes and drain pipes

9.1. Refrigerant piping work

This piping work must be done in accordance with the installation manuals for both
outdoor unit and BC controller (simultaneous cooling and heating series R2).
• Series R2 is designed to operate in a system that the refrigerant pipe from an out-
door unit is received by BC controller and branches at the BC controller to connect
between indoor units.
• For constraints on pipe length and allowable difference of elevation, refer to the
outdoor unit manual.
• The method of pipe connection is brazing connection.
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.5)
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.5)
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.
12
PWFY-P100VM-E-BU
ø15.88
ø9.52
More than 10 mm
B Refrigerant piping (liquid)
D Water outlet
*1: PWFY-P140VM-E1/E2-AU
B Pull out insulation
D Return to original position
F Wrap with insulating tape
[Fig. 7.4.3] (P.4)
Board
TB141A OUT1
L
F
52
P
AC220V ~ 240V
1 2 3 L
TB1
F: Fuze
52P: Magnetic contactor for heat source water pump
and thickness given below) onto both liquid and gas pipes.
Be also sure to wind commercially available insulating material (with a form polyeth-
ylene's specific gravity of 0.03 and thickness given below) onto all pipes which pass
through rooms.
PWFY-P140VM-E1/E2-AU
ø15.88
ø9.52
ø32
3 If there are customer's specifications, simply follow them.
 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.

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)
AC220V ~ 240V
or
DC30V or less
L
N
PWFY
Solenoid
valve kit
N
TB2
WP
MCB: Circuit breaker
WP: Water pump
N
MCB
52P