1. Safety Considerations
Read these SAFETY CONSIDERATIONS carefully before
performing any repair work. Comply with these safety symbols
Meanings of DANGER, WARNING, CAUTION, and NOTE
DANGER .............. Indicates an imminently hazardous
situation which, if not avoided, will
result in death or serious injury.
WARNING ............ Indicates a potentially hazardous
situation which, if not avoided, could
result in death or serious injury.
CAUTION ............. Indicates a potentially hazardous
situation which, if not avoided, may
result in minor or moderate injury. It
may also be used to alert against
NOTE .................. Indicates situations that may result in
equipment or property-damage
Safety Considerations for Repair
• If refrigerant gas leaks during repair or service, ventilate
the area immediately. Refrigerant gas may produce toxic
gas if it comes into contact with flames. Refrigerant gas
is heavier than air and replaces oxygen. In the event of
an accident, a massive leak could lead to oxygen
depletion, especially in basements, and an asphyxiation
hazard could occur leading to serious injury or death.
• Do not start or stop the air conditioner or heat pump
operation by plugging or unplugging the power cable
plug if a plug is used. Plugging or unplugging the
power cable plug to operate the equipment may cause
an electrical shock or fire.
• Use parts listed in the service parts list and
appropriate tools to conduct repair work. The use of
inappropriate parts or tools may cause an electrical
shock or fire.
• Disconnect power before disassembling the
equipment for repairs. Working on the equipment that
is connected to the power supply may cause an
electric shock. If it is necessary to supply power to the
equipment to conduct repairs or to inspect the
circuits, do not touch any electrically charged
sections of the equipment.
• The step-up capacitor supplies high-voltage
electricity to the electrical components of the outdoor
unit. Discharge the capacitor completely before
conducting repair work. A charged capacitor may
cause an electrical shock.
• If refrigerant gas is discharged during repair work, do
not touch the discharged refrigerant gas. The
refrigerant gas may cause frostbite.
• Use only pipes, flare nuts, tools, and other materials
designed specifically for R410A refrigerant systems.
Never use tools or materials designed for R22
refrigerant systems on an R410A refrigerant system.
Doing so can cause a serious accident or an
• Check to see if the parts and wires are mounted and
connected properly, and if the connections at the
soldered or crimped terminals are secure. Improper
installation and connections may cause excessive
heat generation, fire, or electrical shock.
• Prior to disconnecting the suction or discharge pipe
from the compressor at the welded section,
pump-down the refrigerant gas completely in a well-
ventilated place first. If there is refrigerant gas or oil
remaining inside the compressor, the refrigerant gas or
oil can discharge when the pipe is being disconnected
and it may cause an injury.
• Wear a safety helmet, gloves, and a safety belt when
working at an elevated height of more than 6.5 ft (2 m).
Insufficient safety measures may cause a fall resulting in
• Do not mix air or gas other than the specified
refrigerant R410A to the refrigerant system. If air
enters the refrigerant systems, it can cause an
excessive high pressure resulting in equipment
damage and injury.
• When relocating the equipment, check if the new
installation site has sufficient strength to withstand
the weight of the equipment. If the installation site
does not have sufficient strength and the equipment
is not properly secured, the equipment may fall and
• Securely fasten the outside unit terminal cover
(panel). If the terminal cover/panel is not fastened
properly, dust or water may enter the outside unit
causing fire or electric shock.
• When relocating the system, keep the refrigerant
circuit free from substances other than the specified
refrigerant (R-410A) such as air. Any presence of air or
other foreign substance in the refrigerant circuit can
cause an abnormal pressure rise or rupture, resulting
• If refrigerant gas leaks, locate the leaking point and
repair it before charging refrigerant. After charging
refrigerant, check for refrigerant leaks. If the leaking
point cannot be located and the repair work must be
stopped, perform a pump-down and close the service
valve to prevent the refrigerant gas from leaking into
the room. The refrigerant gas itself is harmless, but it