Precautions For Devices That Use R410A Refrigerant; Before Installation; Before Installation (Relocation) - Electrical Work; Before Starting The Test Run - Mitsubishi Electric City Multi PURY-EP-YJM-A Installation Manual

1.2. Precautions for devices that use
R410A refrigerant
Caution:
• Do not use existing refrigerant piping.
- The old refrigerant and refrigerant oil in the existing piping contains a large
amount of chlorine which may cause the refrigerant oil of the new unit to
deteriorate.
- R410A is a high-pressure refrigerant and can cause the existing piping to
burst.
• Use refrigerant piping made of phosphorus deoxidized copper and
copper alloy seamless pipes and tubes. In addition, be sure that the
inner and outer surfaces of the pipes are clean and free of hazardous
sulphur, oxides, dust/dirt, shaving particles, oils, moisture, or any other
contaminant.
- Contaminants on the inside of the refrigerant piping may cause the
refrigerant oil to deteriorate.
• Store the piping to be used during installation indoors and keep both
ends of the piping sealed until just before brazing. (Store elbows and
other joints in a plastic bag.)
- If dust, dirt, or water enters the refrigerant cycle, deterioration of the oil and
compressor failure may result.
• Apply a small amount of ester oil, ether oil, or alkyl benzene to fl ares.
(for indoor unit)
- Infi ltration of a large amount of mineral oil may cause the refrigerant oil to
deteriorate.
• Use liquid refrigerant to fi ll the system.
- If gas refrigerant is used to fi ll the system, the composition of the
refrigerant in the cylinder will change and performance may drop.
• Do not use a refrigerant other than R410A.
- If another refrigerant (R22, etc.) is mixed with R410A, the chlorine in the
refrigerant may cause the refrigerant oil to deteriorate.
• Use a vacuum pump with a reverse fl ow check valve.
- The vacuum pump oil may fl ow back into the refrigerant cycle and cause
the refrigerant oil to deteriorate.
• Do not use the following tools that are used with conventional
refrigerants.
(Gauge manifold, charge hose, gas leak detector, reverse fl ow check
valve, refrigerant charge base, refrigerant recovery equipment)
- If the conventional refrigerant and refrigerant oil are mixed in the R410A,
the refrigerant may deteriorate.
- If water is mixed in the R410A, the refrigerant oil may deteriorate.
- Since R410A does not contain any chlorine, gas leak detectors for
conventional refrigerants will not react to it.
• Do not use a charging cylinder.
- Using a charging cylinder may cause the refrigerant to deteriorate.
• Be especially careful when managing the tools.
- If dust, dirt, or water gets into the refrigerant cycle, the refrigerant may
deteriorate.

1.3. Before installation

Caution:
• Do not install the unit where combustible gas may leak.
- If the gas leaks and accumulates around the unit, an explosion may result.
• Do not use the air conditioner where food, pets, plants, precision
instruments, or artwork are kept.
- The quality of the food, etc. may deteriorate.
• Do not use the air conditioner in special environments.
- Oil, steam, sulfuric smoke, etc. can signifi cantly reduce the performance of
the air conditioner or damage its parts.
• When installing the unit in a hospital, communication station, or similar
place, provide suffi cient protection against noise.
- Inverter equipment, private power generator, high-frequency medical
equipment, or radio communication equipment may cause the air
conditioner to operate erroneously, or fail to operate. On the other hand,
the air conditioner may affect such equipment by creating noise that
disturbs medical treatment or image broadcasting.
• Do not install the unit on or over things that are subject to water
damage.
- When the room humidity exceeds 80% or when the drain pipe is clogged,
condensation may drip from the indoor unit. Perform collective drainage
work together with the outdoor unit, as required.
12
1.4. Before installation (relocation) -
electrical work
Caution:
• Ground the unit.
- Do not connect the ground wire to gas or water pipes, lightning rods, or
telephone ground lines. Improper grounding may result in electric shock.
• Never connect in reverse phases.
Never connect the Power Line L1, L2, and L3 to Terminal N.
- If the unit is miss wired, when power is supplied, some electrical parts will
be damaged.
• Install the power cable so that tension is not applied to the cable.
- Tension may cause the cable to break and generate heat and cause a fi re.
• Install a leak circuit breaker, as required.
- If a leak circuit breaker is not installed, electric shock may result.
• Use power line cables of suffi cient current carrying capacity and rating.
- Cables that are too small may leak, generate heat, and cause a fi re.
• Use only a circuit breaker and fuse of the specifi ed capacity.
- A fuse or circuit breaker of a larger capacity, or the use of a substitute
simple steel or copper wire may result in a general unit failure or fi re.
• Do not wash the air conditioner units.
- Washing them may cause an electric shock.
• Be careful that the installation base is not damaged by long use.
- If the damage is left uncorrected, the unit may fall and cause personal
injury or property damage.
• Install the drain piping according to this Installation Manual to ensure
proper drainage. Wrap thermal insulation around the pipes to prevent
condensation.
- Improper drain piping may cause water leakage and damage to furniture
and other possessions.
• Be very careful about transporting the product.
- One person should not carry the product. Its weight is in excess of 20kg.
- Some products use PP bands for packaging. Do not use any PP bands as
a means of transportation. It is dangerous.
- Do not touch the heat exchanger fi ns. Doing so may cut your fi ngers.
- When transporting the outdoor unit, support it at the specifi ed positions on
the unit base. Also support the outdoor unit at four points so that it cannot
slip sideways.
• Safely dispose of the packing materials.
- Packing materials, such as nails and other metal or wooden parts, may
cause stabs or other injuries.
- Tear apart and throw away plastic packaging bags so that children will not
play with them. If children play with a plastic bag which has not been torn
apart, they face the risk of suffocation.

1.5. Before starting the test run

Caution:
• Turn on the power at least 12 hours before starting operation.
- Starting operation immediately after turning on the main power switch
can result in irreversible damage to internal parts. Keep the power switch
turned on during the operational season. Make sure of the phase order of
power supply and voltage between each phase.
• Do not touch the switches with wet fi ngers.
- Touching a switch with wet fi ngers can result in an electric shock.
• Do not touch the refrigerant pipes during and immediately after
operation.
- During and immediately after operation, the refrigerant pipes may be hot
or cold, depending on the condition of the refrigerant fl owing through the
refrigerant piping, compressor, and other refrigerant cycle parts. Your
hands may suffer burns or frostbite if you touch the refrigerant pipes.
• Do not operate the air conditioner with the panels and guards removed.
- Rotating, hot, or high-voltage parts can cause injuries.
• Do not turn off the power immediately after stopping operation.
- Always wait at least 5 minutes before turning off the power. Otherwise,
drainage water leakage or mechanical failure of sensitive parts may occur.
• Do not touch the surface of the compressor during servicing.
- If unit is connected to a supply and not running, the crank case heater
located at the base of the compressor may still be operating.