Safety Precaution - Mitsubishi Electric PKFY-P32VGM-E Technical & Service Manual

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SAFETY PRECAUTION

CAUTIONS RELATED TO NEW REFRIGERANT
Cautions for units utilizing refrigerant R407C
Do not use the existing refrigerant piping.
The old refrigerant and lubricant in the existing piping
contains a large amount of chlorine which may cause the
lubricant deterioration of the new unit.
Use "low residual oil piping"
If there is a large amount of residual oil (hydraulic oil, etc.)
inside the piping and joints, deterioration of the lubricant
will result.
Store the piping to be used during installation
indoors with keep both ends 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 trouble may result.
Use ESTR , ETHER or HAB as the lubricant to
coat flares and flange connection parts.
If large amount of mineral oil enter, that can cause
deterioration of refrigerant oil etc.
[1] Cautions for service
·After recovering the all refrigerant in the unit, proceed to working.
·Do not release refrigerant in the air.
·After completing the repair service, recharge the cycle with the specified amount of
liquid refrigerant.
[2] Refrigerant recharging
(1) Refrigerant recharging process
1Direct charging from the cylinder.
·R407C cylinder are available on the market has a syphon pipe.
·Leave the syphon pipe cylinder standing and recharge it.
(By liquid refrigerant)
Gravimeter
(2) Recharge in refrigerant leakage case
·After recovering the all refrigerant in the unit, proceed to working.
·Do not release the refrigerant in the air.
·After completing the repair service, recharge the cycle with the specified amount of
liquid refrigerant.
Use liquid refrigerant to seal 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 R407C.
If another refrigerant (R22, etc.) is used, the chlorine in the
refrigerant may cause the lubricant deterioration.
Use a vacuum pump with a reverse flow check valve.
The vacuum pump oil may flow back into the refrigerant
cycle and cause the lubricant deterioration.
Ventilate the room if refrigerant leaks during
operation. If refrigerant comes into contact with
a flame, poisonous gases will be released.
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