Mitsubishi Electric PUHY-M200YNW-A1 Service Handbook page 2

Safety Precautions
Read and observe the safety precautions below and the instructions provided on the labels affixed to the unit.
Retain this manual for future reference. Make sure that this manual is passed on to the end users.
All refrigerant piping work, electrical work, air-tightness test, and brazing work must be performed by qualified personnel.
Incorrect use may result in serious injury.
[1] General Precautions
General Precautions
Do not use any refrigerant other than the
type indicated in the manuals for the unit
and on the nameplate.
Doing so will cause the unit or pipes to burst, or result
in an explosion or fire during use, during repairs, 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 result-
ing from the use of the wrong type of refrigerant.
Do not use the unit in an unusual environ-
ment.
If the unit is used in areas exposed to large amounts of
oil, steam, organic solvents, or corrosive gases (such
as ammonia, sulfuric compounds, or acids), or areas
where acidic/alkaline solutions or special chemical
sprays are used frequently, it may significantly reduce
the performance and corrode the internal parts, result-
ing in refrigerant leakage, water leakage, injury, elec-
tric shock, malfunction, smoke, or fire.
Do not change the settings of the safety or
protection devices.
Forcing the unit to operate by disabling the safety de-
vices, such as the pressure switch or the thermal
switch, may result in bursting, fire, or explosion.
Operating the unit with a safety device whose settings
have been changed may result in bursting, fire, or ex-
plosion.
Using safety devices other than those specified by Mit-
subishi Electric may result in bursting, fire, or explo-
sion.
Do not alter or modify the unit.
Doing so will result in refrigerant leakage, water leak-
age, serious injury, electric shock, or fire.
indicates a hazardous situation which, if not avoided, could result in
death or serious injury.
indicates a hazardous situation which, if not avoided, could result in
minor or moderate injury.
addresses practices not related to personal injury, such as product
and/or property damage.
Do not wet the electrical parts.
Doing so may result in current leakage, electric shock,
malfunction, or fire.
Do not touch the electrical parts, switches,
or buttons with wet fingers.
Doing so may result in electric shock, malfunction, or
fire.
Do not touch the refrigerant pipes and re-
frigerant line components with bare hands
during and immediately after operation.
The refrigerant in the pipes will be very hot or very cold,
resulting in frostbite or burns.
Do not touch the electrical parts with bare
hands during and immediately after opera-
tion.
Doing so may result in burns.
Ventilate the room while servicing the unit.
If the refrigerant leaks, oxygen deficiency may result. If
the leaked refrigerant comes in contact with a heat
source, toxic gas will be generated.
If you notice any abnormality (e.g., a burn-
ing smell), stop the operation, turn off the
power switch, and consult your dealer.
Continuing the operation may result in electric shock,
malfunction, or fire.
Properly install all required covers and pan-
els on the terminal box and the control box.
If dust or water enters the unit, this may result in electric
shock or fire.
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