CAUTION
Risks related to PAA unit installation
• When installing and relocating the PAA unit, do not charge it with a refrigerant different
from the refrigerant specified on the unit.
– If a different refrigerant or air is mixed with the original refrigerant, the refrigerant cycle
may malfunction and the unit may be damaged. Use only recommended refrigerant
specified in ODU manual for system operation (ONLY R410A).
• The PAA unit is designed for indoor installation only.
• The PAA unit must be installed downstream (discharge air) side of the furnace.
• Do not alter the cabinet or braze inside the cabinet. Quench all brazed joints with water
or a wet rag to avoid overheating after brazing.
– It may affect the performance of the PAA unit.
• Do not use leak detection additive.
– ODU and PAA unit parts may be damaged by the refrigerant/additive mixture.
Refrigerant leak risks
• The installer (technician) shall ensure there is no refrigerant leakage according to local
regulations and standards.
– Refrigerant leakage may affect the performance of the heat pump.
Install guidelines
• For PAA unit piping connections, use flare connection as the equipment was designed
for. Mitsubishi Electric US, Inc. is not responsible for brazing connection done by the
installer.
– Brazing connections may cause damage to the PAA unit.
Specifications are subject to change without notice.
PAA-A18, 24, 30, 36, 42AA1/BA1/CA1
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