Safety Precaution - Mitsubishi Electric MXZ-2F33VF4-E1 Service Manual

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SAFETY PRECAUTION

MEANINGS OF SYMBOLS DISPLAYED ON THE UNIT
WARNING
Read the OPERATION MANUAL carefully before operation.
Service personnel are required to carefully read the OPERATION MANUAL and INSTALLATION MANUAL before operation.
Further information is available in the OPERATION MANUAL, INSTALLATION MANUAL, and the like.
2-1. ALWAYS OBSERVE FOR SAFETY
Before obtaining access to terminal, all supply circuits must be disconnected.
2-2. CAUTIONS RELATED TO NEW REFRIGERANT
Cautions for units utilizing refrigerant R32
Preparation before the repair service.
• Prepare the proper tools.
• Prepare the proper protectors.
• Provide adequate ventilation.
• After stopping the operation of the air conditioner, turn off
the power-supply breaker.
• Discharge the condenser before the work involving the
electric parts.
Use new refrigerant pipes.
In case of using the existing pipes for R22, be careful with
the following.
· Be sure to clean the pipes and make sure that the insides
of the pipes are clean.
· Change flare nut to the one provided with this product.
Use a newly flared pipe.
· Avoid using thin pipes.
Make sure that the inside and outside of refrige-
rant piping is clean and it has no contaminants
such as sulfur, oxides, dirt, shaving particles, etc,
which are hazard to refrigerant cycle.
In addition, use pipes with specified thickness.
Contamination inside refrigerant piping can cause deterio-
ration of refrigerant oil, etc.
Store the piping indoors, and both ends of the
piping sealed until just before brazing.
(Leave elbow joints, etc. in their packaging.)
If dirt, dust or moisture enters into refrigerant cycle, that can
cause deterioration of refrigerant oil or malfunction of com-
pressor.
OBH790L
This mark is for R32 refrigerant only. Refrigerant type is written on nameplate of outdoor unit.
Precautions during the repair service.
• Do not perform the work involving the electric parts
with wet hands.
• Do not pour water into the electric parts.
• Do not touch the refrigerant.
• Do not touch the hot or cold areas in the refrigerating cycle.
• When the repair or the inspection of the circuit needs to be
done without turning off the power, exercise great caution
not to touch the live parts.
• When opening or closing the valve below freezing
temperatures, refrigerant may spurt out from the valve gap,
resulting in injuries.
Use a vacuum pump with a reverse flow check
valve.
Vacuum pump oil may flow back into refrigerant cycle and
that can cause deterioration of refrigerant oil, etc.
Use the following tools specifically designed for
use with R32 refrigerant.
The following tools are necessary to use R32 refrigerant.
Gauge manifold
Charge hose
Gas leak detector
Torque wrench
Handle tools with care.
If dirt, dust or moisture enters into refrigerant cycle, that can
cause deterioration of refrigerant oil or malfunction of com-
pressor.
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Tools for R32
Flare tool
Size adjustment gauge
Vacuum pump adaptor
Electronic refrigerant
charging scale