5.5. Before starting the test run
CAUTION
• Open the stop valves isolating the PAA unit from the outdoor unit before starting
operation to avoid refrigerant pipe bursting during furnace operation.
• Turn on the power at least 12 hours before starting operation.
– Starting operation immediately after turning on the main power switch can result
in severe damage to internal parts. Keep the power switch turned on during the
operational season.
• Do not turn off the power immediately after stopping operation. Wait at least five minutes
before turning off the power.
– Turning off the power immediately may cause a water to leak.
WARNING
• Do not touch the switches with wet fingers.
– Touching a switch with wet fingers can cause electric shock.
• Do not touch the refrigerant pipes during and immediately after operation.
– During and immediately after operation, the refrigerant pipes may be extremely hot
or cold, depending on the condition of the refrigerant flowing through the refrigerant
piping, compressor, and other refrigerant cycle parts. Your hands may suffer burns or
frostbite if you touch the refrigerant pipes.
• Read the chapters from the "Selecting an installation site" chapter to the "Electrical
wiring" chapter carefully before operating the equipment. Do not operate the furnace,
PAA unit or outdoor unit with the panel or guard removed.
– Injury may occur if you touch the rotating fan of the furnace or outdoor unit, high-
temperature parts such as compressors and pipes, or high-voltage parts such as
terminal blocks.
• Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this
or any other appliance.
• What to do if you smell gas?
– Do not touch any electrical switch.
– Do not use any phone in your building.
– Immediately call your gas supplier from a neighboring location.
– Follow the gas supplier's instructions.
– If you cannot reach your gas supplier, call the fire department.
– Do not try to light any appliance.
• Never use an open flame to detect refrigerant leaks. Explosive conditions may occur.
Use a leak test sensor or other approved methods for leak testing. Should furnace
discharge air supply overheating occur and the gas supply fails to shut off, follow the
furnace installation manual to disable the gas and electric supply to the furnace.
Specifications are subject to change without notice.
PAA-A18, 24, 30, 36, 42AA1/BA1/CA1
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