Selecting An Installation Site; Securing Installation And Service Space; Installing The Unit; Fixing Unit - Mitsubishi Electric PFAV-P250VM-E Manuel D'installation

3. Selecting an installation site

• Select a location so that air can be blown into all corners of the room.
• Avoid locations exposed to outside air.
• Select a location free of obstructions to the airflow in and out of the unit.
• Avoid locations exposed to steam or oil vapour.
• Avoid locations where combustible gas may leak, settle or be generated.
• Avoid installation near machines emitting high-frequency waves (high-
frequency welders, etc.).
• Avoid locations where the airflow is directed at a fire alarm sensor. (Hot air
could trigger the alarm during the heating operation.)
• Avoid places where acidic solutions are frequently handled.
• Avoid places where sulphur-based or other sprays are frequently used.
• Avoid an atmosphere containing corrosive gases or organic solvents.
• Operation in a very hot and humid atmosphere (dew point of 23°C or more)
for a long period of time may cause condensation to form in the indoor unit. If
there is a likelihood of the indoor unit being used under such conditions, add
heat insulation material (10 to 20 mm) to the whole front of the indoor unit in
order to prevent condensation.
• When the indoor unit is installed in a machine room and connected by a duct,
and the atmosphere in the machine room becomes very hot and humid,
condensation may form in the indoor unit. In such a case, take measures
such as circulating the air in the machine room and the air inside the room in
order to lower the temperature and humidity within the machine room.
• If the indoor unit is installed in a room that is very air tight, negative pressure
builds up inside the room, resulting in problems such as the inability to open
the door, so provide ventilation holes to prevent the build up of negative
pressure in the room.
Warning:
Install the indoor unit on a strong enough to sustain its weight.
If not enough, it may cause the unit to fall down, resulting in an injury.

3.1. Securing installation and service space

[Fig. 3.1.1] (P.2)
P250·P500 models
A Separately sold plenum chamber (not compatible with the Fresh air intake
models)
B (Front space)

4. Installing the unit

4.1. Fixing unit

• Do not unpack indoor units until they have been transported to the installation site.
• Install anchor bolts (locally procured).
Anchor bolt size
P250, P500, P300-F, P600-F : ø8 (M8 screw)
P750, P900-F : ø10 (M10 screw)
• Be sure to install indoor units on a level surface. Since the center of gravity of
the unit is in the middle of the unit, if the units are tilted they may fall.
Caution when connecting a duct
• Install a canvas duct between the unit and the duct.
• Use non-flammable parts for the duct.
• Provide sufficient heat/sound insulation to ducts and flanges.
• Avoid using ducts made of flexible aluminum or similar lightweight materials.
They may vibrate and produce noise.
Notes on when an optional plenum chamber is installed
The unit described in this manual is designed to be used with a duct. When an
Optional plenum chamber is used, an adjustment of the pulley is required.
• Refer to the manual that came with the plenum chamber for how to install it.
Notes on how to remove the top front panel on the unit (P250·P500·
P300-F·P600-F)
Before removing the top front panel (panel with a built-in remote controller) to
adjust or replace the pulley or belt, remote controller cables need to be
disconnected.
Take the following procedures to remove the panel.
(1) Loosen the two securing screws on the bottom front panel, and remove
the panel by pulling the panel up and forward.
(2) Disconnect the remote controller connector A in [Fig. 4.1.1].
* Be sure to disconnect the connector before removing the top front
panel to prevent the remote controller cable from being damaged.
(3) Remove the two fixing screws on the top front panel and pull open the
panel bottom, and then pull up the remote controller cable (connector A).
C Remote controller cable hole (to outdoor unit)
D Power cable hole (for 380V or more)
E Equipment power cable hole
F Wood base
G Duct space (if a duct is connected)
H Refrigerant pipes
I Drain pipe
[Fig. 3.1.2] (P.2)
P300-F·P600-F models
A Remote controller cable hole (to outdoor unit)
B Power cable hole (380V or more)
C Equipment power cable hole
D Wood base
E Refrigerant pipe hole
F Drain pipe hole
G Duct space
H (Front space)
[Fig. 3.1.3] (P.2)
P750·P900-F models
A (Front space)
B Remote controller cable hole (to outdoor unit)
C Power cable hole (for 380V or more)
D Refrigerant pipe inlet (gas)
E Wood base
F Refrigerant pipe inlet (liquid)
• Select a location with a strong floor and use a wood base with a thickness of
85 mm or more to make drainage easier and suppress the transmission of
vibration from the air conditioner to the floor.
* Separately secure sufficient space to perform installation work such as
piping and wiring work.
* If the indoor unit is installed in a room that is very air tight, negative
pressure builds up inside the room, resulting in problems such as the
inability to open the door, so provide ventilation holes to prevent the build
up of negative pressure in the room.
(4) Pull up the top front panel to remove it.
* Use caution not to place the panel on the cables or connector.
Note: Support the bottom front panel to prevent it from falling forward
when removing the securing screws.
Requests Regarding Confirming Pulley Parallelism and Belt Tension
Confirm the state of pulley parallelism and belt tension during installation
(refer to the section 4.2., "Pulley Parallelism and Belt Tension" on page 14).
* Inappropriate pulley parallelism and belt tension may cause an abnormal
noise to be generated or other trouble.
[Fig. 4.1.1] (P.2)
A Top front panel
C Connector A
E Bottom front panel

4.2. Requests regarding pulleys and belts

Adjusting the width of variable-width pulley
* Applicable to the P250·P300-F models
Adjust the PC ø of variable-width pulley according to the procedures described
below.
(1) Loosen the setscrew holding the fixed and the sliding discs in place.
(2) Turn the sliding disc counter-clockwise until no gap is left (0 mm) between
the fixed and the sliding discs.
(3) Select the PC ø in Table 1 of [Fig. 4.2.1] that is closest to the one to be
used. Once the PC ø has been selected, see the number of turns to apply
(Table 1) that corresponds to the selected PC ø to determine how many
turns to apply to the sliding disc.
(4) Fix the fixed and the sliding discs in place with the setscrew. (Tightening
torque: 13.5N·m)
Let the tip of the setscrew rest in the V-shaped notch on the flat part of the
fixed disc to hold the sliding disc in position.
Apply Screw Lock (field supplied) to the setscrew to keep it from coming
unscrewed. (Screw Lock: ThreeBond 1322N or its equivalent)
B Remote controller
D Securing screws
13