Safety Precaution - Mitsubishi Electric PUHZ-W90VHA Service Manual

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SAFETY PRECAUTION

1-1. ALWAYS OBSERVE FOR SAFETY
Before obtaining access to terminal, all supply ciucuits must be disconnected.
1-2. CAUTIONS RELATED TO NEW REFRIGERANT
Cautions for units utilizing refrigerant R410A
Do not use refrigerant other than R410A.
If other refrigerant (R22 etc.) is used, chlorine in refrigerant can cause deterioration of refrigerant oil etc.
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 R410A refrigerant.
The following tools are necessary to use R410A refrigerant.
Tools for R410A
Gauge manifold
Charge hose
Gas leak detector
Torque wrench
Keep tools with care.
If dirt, dust or moisture enters into refrigerant cycle, that can cause deterioration of refrigerant oil or malfunction
of compressor.
Do not use a charging cylinder.
If a charging cylinder is used, the composition of refrigerant will change and the efficiency will be lowered.
Ventilate the room if refrigerant leaks during operation. If refrigerant comes into contact with
a flame, poisonous gases will be released.
Charge refrigerant from liquid phase of gas cylinder.
If the refrigerant is charged from gas phase, composition change may occur in refrigerant and the efficiency
will be lowered.
[1] Cautions for service
(1) Perform service after recovering the refrigerant left in unit completely.
(2) Do not release refrigerant in the air.
(3) After completing service, charge the cycle with specified amount of refrigerant.
[2] Additional refrigerant charge
When charging directly from cylinder
· Check that cylinder for R410A on the market is syphon type.
· Charging should be performed with the cylinder of syphon stood vertically. (Refrigerant is charged from liquid phase.)
Vacuum pump adaptor
Electronic refrigerant
charging scale
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