Precautions For Indoor Unit And Bc Controller - Mitsubishi Electric CITY MULTI PURY-HP72TNU-A Data Book

1. Installation information
1-1-6. Unit installation
Your local distributor or a qualified technician must read the Installation Manual that is provided with each unit carefully
before performing installation work.
Consult 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.
Ensure there is enough space around each unit.
1-1-7. Optional accessories
Only 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.
Some 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.
Note that some optional accessories may affect the air conditioner's external form, appearance, weight, operating
sound, and other characteristics.
1-1-8. Operation/Maintenance
Read the Instruction Book that is provided with each unit carefully prior to use.
Maintenance 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.

1-2. Precautions for Indoor unit and BC controller

1-2-1. Operating environment
The 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.
If the units operate in the cooling mode at the humidity above 80%, condensation may collect and drip from the indoor
units.
1-2-2. Unit characteristics
The return air temperature display on the remote controller may differ from the ones on the other thermometers.
The clock on the remote controller may be displayed with a time lag of approximately one minute every month.
The 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.
Use 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.
The room temperature may rise drastically due to Thermo OFF in the places where the air conditioning load is large
such as computer rooms.
Be sure to use a regular filter. If an irregular filter is installed, the unit may not operate properly, and the operation noise
may increase.
The room temperature may rise over the preset temperature in the environment where the heating air conditioning load
is small.
1-2-3. Unit installation
For simultaneous cooling/heating operation type air conditioners (R2, H2i R2, WR2 series), the G-type BC controller
cannot be connected to the P144 outdoor/heat source unit model or above, and the G- and GA-type BC controllers
cannot be connected to the P264 model or above. The GB- and HB-type BC controllers (sub) cannot be connected to
the outdoor/heat source unit directly, and be sure to use them with GA- and HA-type BC controllers (main).
The insulation for low pressure pipe between the BC controller and outdoor/heat source 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.
Do not have any branching points on the downstream of the refrigerant pipe header.
When 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.
When indoor units operate a fresh air intake, install a filter in the duct (field-supplied) to remove the dust from the air.
The 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.
Operating fresh air intake on the indoor unit may increase the sound pressure level.
MEES16K099
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