1.2. Precautions for devices that use R410A
and R32 refrigerants
Warning:
• Do not use refrigerant other than the type indicated in the manuals pro-
vided 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
malfunctions or accidents resulting from the use of the wrong type of
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 and R32 are high-pressure refrigerants 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
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
compressor failure may result.
• Apply a small amount of ester oil, ether oil, or alkyl benzene to flares. (for
indoor unit)
- Infiltration of a large amount of mineral oil may cause the refrigerant oil to
deteriorate.
• Use liquid refrigerant to fill the system. (R410A only)
- If gas refrigerant is used to fill the system, the composition of the refrigerant
in the cylinder will change and performance may drop.
• Do not use a refrigerant other than R410A or R32.
- If another refrigerant (R22, etc.) is mixed with R410A or R32, the chlorine in
the refrigerant may cause the refrigerant oil to deteriorate.
• The unit that was used with R410A must not be reused with R32, and vice
versa.
• 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 or
R32, the refrigerant may deteriorate.
- If water is mixed in the R410A or R32, the refrigerant oil may deteriorate.
- Since R410A or R32 does not contain any chlorine, gas leak detectors for
conventional refrigerants will not react to it.
• Refrigerant R32 is flammable. Do not use a naked-flame type detector.
• Do not use a charging cylinder.
- Using a charging cylinder may cause the refrigerant to deteriorate.
• Do not use antioxidant or leak-detection additive.
• Be especially careful when managing the tools.
- If dust, dirt, or water gets into the refrigerant cycle, the refrigerant may
deteriorate.
• The unit shall be properly stored to prevent mechanical damage.
• When using R32, check for refrigerant leaks before service.
- If the refrigerant leaks, fire may result.
• Do not open the control box cover when recovering, charging, or purging
R32 refrigerant.
- Doing so may cause sparks, resulting in fire.
• When using R32, store the unit in a room large enough to allow clearance
in the event of refrigerant leakage.
• Carry a refrigerant leak detection sensor when installing or removing the
unit that uses R32.
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 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.
8
• When installing the unit in a hospital, communication station, or similar
place, provide sufficient 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 or BC controller. Perform
collective drainage work together with the outdoor unit, as required.
• Make sure to remove the foamed styrol between the unit and the drain
pan.
• Do not install the unit where corrosive gas may be generated.
- Doing so can corrode the pipes, resulting in refrigerant leakage and fire.
• Check that markings of the unit are not illegible.
- Illegible warning or caution markings may cause damage to the unit,
resulting in injury.
1.4. Before installation (relocation) - electri-
cal 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.
• 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 the use of substitute simple
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
condensation.
- Improper drain piping may cause water leakage causing 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 20 kg.
- Some products use PP bands for packaging. Do not use any PP bands as a
means of transportation. It is dangerous.
• 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.
• Do not touch the switches with wet fingers.
- Touching a switch with wet fingers 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 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 5 minutes before turning off the power. Otherwise,
drainage water leakage or mechanical failure of sensitive parts may occur.