Mitsubishi Electric PURY-WP-YJM-A Data Book page 217

6. Installation information
6-1-6. Unit installation
ŒYour local distributor or a qualified technician must read the Installation Manual that is provided with each unit carefully
before performing installation work.
ŒConsult your local distributor or a qualified technician when installing the unit. Improper installation by an unqualified
person may result in water leakage, electric shock, or fire.
ŒEnsure there is enough space around each unit.
6-1-7. Optional accessories
ŒOnly use accessories recommended by Mitsubishi Electric. Consult your local distributor or a qualified technician when
installing them. Improper installation by an unqualified person may result in water leakage, electric leakage, system
breakdown, or fire.
ŒSome optional accessories may not be compatible with the air conditioning unit to be used or may not suitable for the
installation conditions. Check the compatibility when considering any accessories.
ŒNote that some optional accessories may affect the air conditioner's external form, appearance, weight, operating
sound, and other characteristics.
6-1-8. Operation/Maintenance
ŒRead the Instruction Book that is provided with each unit carefully prior to use.
ŒMaintenance or cleaning of each unit may be risky and require expertise. Read the Instruction Book to ensure safety.
Consult your local distributor or a qualified technician when special expertise is required such as when the indoor unit
needs to be cleaned.
6-2. Precautions for Indoor unit
6-2-1. Operating environment
ŒThe refrigerant (R410A) used for air conditioner is non-toxic and nonflammable. However, if the refrigerant leaks, the
oxygen level may drop to harmful levels. If the air conditioner is installed in a small room, measures must be taken to
prevent the refrigerant concentration from exceeding the safety limit even if the refrigerant should leak.
ŒIf the units operate in the cooling mode at the humidity above 80%, condensation may collect and drip from the indoor
units.
6-2-2. Unit characteristics
ŒThe return air temperature display on the remote controller may differ from the ones on the other thermometers.
ŒThe clock on the remote controller may be displayed with a time lag of approximately one minute every month.
ŒThe temperature using a built-in temperature sensor on the remote controller may differ from the actual room tempera-
ture due to the effect of the wall temperature.
ŒUse a built-in thermostat on the remote controller or a separately-sold thermostat when indoor units installed on or in
the ceiling operate the automatic cooling/heating switchover.
ŒThe room temperature may rise drastically due to Thermo OFF in the places where the air conditioning load is large
such as computer rooms.
ŒBe sure to use a regular filter. If an irregular filter is installed, the unit may not operate properly, and the operation noise
may increase.
ŒThe room temperature may rise over the preset temperature in the environment where the heating air conditioning load
is small.
6-2-3. Unit installation
ŒFor simultaneous cooling/heating operation type air conditioners (R2, WR2 series), the G-type BC controller cannot be
connected to the 16HP outdoor unit model or above, and the G- and GA-type BC controllers cannot be connected to the
28HP model or above. The GB- and HB-type BC controllers (sub) cannot be connected to the outdoor unit directly, and
be sure to use them with GA- and HA-type BC controllers (main).
ŒThe insulation for low pressure pipe between the BC controller and outdoor unit shall be at least 20 mm thick. If the unit
is installed on the top floor or in a high-temperature, high-humidity environment, thicker insulation may be necessary.
ŒDo not have any branching points on the downstream of the refrigerant pipe header.
ŒWhen a field-supplied external thermistor is installed or when a device for the demand control is used, abnormal stop of
the unit or damage of the electromagnetic contactor may occur. Consult your local distributor for details.
ŒWhen indoor units operate a fresh air intake, install a filter in the duct (field-supplied) to remove the dust from the air.
ŒThe 4-way or 2-way Airflow Ceiling Cassette Type units that have an outside air inlet can be connected to the duct, but
need a booster fan to be installed at site. Refer to the chapter "Indoor Unit" for the available range for fresh air intake
volume.
ŒOperating fresh air intake on the indoor unit may increase the sound pressure level.
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