1.2. Precautions for devices that use R410A
refrigerant
Warning:
• Do not use refrigerant other than the type indicated in the manuals provided
with the unit and on the nameplate.
- Doing so may cause the unit or pipes to burst, or result in explosion or fire during
use, during repair, or at the time of disposal of the unit.
- It may also be in violation of applicable laws.
- MITSUBISHI ELECTRIC CORPORATION cannot be held responsible for mal-
functions or accidents resulting from the use of the wrong type of refrigerant.
Caution:
• Do not use the 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 deteri-
orate.
- R410A is a high-pressure refrigerant and can cause the existing piping to burst.
• Use refrigerant piping made of C1220 (CU-DHP) phosphorus deoxidized
copper as specified in the JIS H3300 "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
residual 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 com-
pressor trouble may result.
• Use ester oil, ether oil or alkylbenzene (small amount) as the refrigerant oil
to coat flares and flange connections.
- The refrigerant oil will degrade if it is mixed with a large amount of mineral oil.
• Use liquid refrigerant to fill the system.
- If gas refrigerant is used to seal 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 refrig-
erant may cause the refrigerant oil to deteriorate.
• Use a vacuum pump with a reverse flow check valve.
- The vacuum pump oil may flow 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 flow check valve,
refrigerant charge base, refrigerant recovery equipment)
- If the conventional refrigerant and refrigerant oil are mixed in the R410A, the
refrigerant may deteriorated.
- 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 in the refrigerant cycle, the refrigerant may deteriorate.
1.3. Before getting installed
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 instru-
ments, 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 significantly reduce the performance of the
air conditioner or damage its parts.
• When installing the unit in a hospital, communication station, or similar
place, provide sufficient protection against noise.
- The inverter equipment, private power generator, high-frequency medical equip-
ment, or radio communication equipment may cause the air conditioner to oper-
ate 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 a structure that may cause leakage.
- When the room humidity exceeds 80 % or when the drain pipe is clogged, con-
densation may drip from the indoor unit. Perform collective drainage work
together with the unit, as required.
8
1.4. Before getting installed (moved) - electri-
cal work
Caution:
• Ground the unit.
- Do not connect the ground wire to gas or water pipes, lightning rods, or tele-
phone ground lines. Improper grounding may result in electric shock.
• 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 fire.
• Install a leak circuit breaker, as required.
- If a leak circuit breaker is not installed, electric shock may result.
• Use power line cables of sufficient current carrying capacity and rating.
- Cables that are too small may leak, generate heat, and cause a fire.
• Use only a circuit breaker and fuse of the specified capacity.
- A fuse or circuit breaker of a larger capacity or a steel or copper wire may result
in a general unit failure or fire.
• 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 con-
densation.
- Improper drain piping may cause water leakage and damage to furniture and
other possessions.
• Be very careful about product transportation.
- Only one person should not carry the product if it weighs more than 20 kg.
- Some products use PP bands for packaging. Do not use any PP bands for a
means of transportation. It is dangerous.
- When transporting the unit, support it at the specified positions on the unit base.
Also support the unit at four points so that it cannot slip side ways.
• 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 was not torn apart, they face
the risk of suffocation.
1.5. Before starting the test run
Caution:
• Error code "7130" appears when both of the following conditions are met.
- The PWFY unit is connected to the outdoor unit of Y series.
- The version of the software is the one listed below.
PWFY series: earlier than Ver. 1.13
Y(YHM) series: earlier than Ver. 12.27
Y(YJM) series: earlier than Ver. 1.31
Replace Y(YJM) series: earlier than Ver. 11.31
HP(ZUBADAN) series: earlier than Ver. 22.27
WY series: earlier than Ver. 12.29
• 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 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 are may be hot
and may be 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.
• 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 five minutes before turning off the power. Otherwise, water
leakage and trouble may occur.
• Do not touch the surface of the compressor during servicing.
- If unit is connected to the supply and not running, crank case heater at compres-
sor is operating.
• Do not touch the panels near the fan exhaust outlet with bare hands: they
can get hot while the unit is in operation (even if it is stopped) or immedi-
ately after operation and poses a risk of burns. Wear gloves to protect your
hands when it is necessary to touch the panels.
• While the unit is in operation or immediately after operation, high-tempera-
ture exhaust air may blow out of the fan exhaust outlet. Do not hold your
hands over the outlet or touch the panels near the outlet.
• Be sure to provide a pathway for the exhaust air from the fan.
• Water pipes can get very hot, depending on the preset temperature. Wrap
the water pipes with insulating materials to prevent burns.