Health, Safety, And Handling - Fisher & Paykel RX256DT4X1 FP Service Manual

13.10.5

Health, Safety, and Handling

Health, safety and handling considerations for HFC134A are virtually no different than those for older
CFC12/R12.
To minimize contamination, exercise extreme care when servicing HFC134A sealed systems.
• No trace of other refrigerants is allowed in HFC134a systems. Chlorinated molecules in other
refrigerants such as CFC12, etc. will lead to capillary tube plugging.
• Ester oil is used in HFC134a systems. Do not use mineral oil.
cannot be mixed. If mineral oils were used in HFC134a systems, lubricant would not return to
compressor and would cause early compressor failure. If significant amount of oil has been lost
from compressor, replace oil rather than adding oil.
• Ester oils used in HFC134a systems are so hydroscopic that by the time an inadequate system
performance is detected, oil will be saturated with moisture.
• CFC12 has much higher tolerance to system processing materials, such as drawing compounds,
rust inhibitors, and cleaning compounds, than HFC134a. Such materials are not soluble in
HFC134a systems. If materials were to be washed from system surfaces by ester oils, they could
accumulate and eventually plug capillary tube.
• Care must be taken to minimize moisture entering HFC134a system. Do not leave compressor or
system open to atmosphere for more than 10 minutes. Excessive moisture in HFC134a system will
react with compressor oil and generate acid.
•
Filter Drier must always be replaced when the system is open for service, dual evacuation is a must.
Important: Unbrazing drier filter from tubing will drive moisture from desiccant and into system,
causing acids to form. Do not unbraze filter drier from tubing. If CFC12 service drier was installed in
HFC134A system, drier could overload due to excessive moisture.
• HFC134a compatible copper tubing must be used when replacing tubing.
CAUTION
101
HFC134a and mineral oils
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