Verify Refrigerant Type In The System - Electrolux Built-in 42" Service Manual

R-134a service information
NOTICE: Instructions given here are furnished as a guide. Persons attempting to use these instructions to make
repairs to the sealed refrigeration system should have a working knowledge of refrigeration and previous training on
sealed system repair.

Verify refrigerant type in the system

CAUTION: R-134a and R-12 are completely
incompatible. Before starting any sealed
system repair, it is extremely important to
check serial plate of product to verify the
type of refrigerant in the system.
Dedicated Equipment
R-134a must not be mixed with other types of
refrigerants. R-134a must be recovered in dedicated and
properly identified recovery bags and tanks.
It will be necessary to check with the manufacturer
of your recovery equipment to determine R-134a
compatibility. Some recovery equipment manufacturers
have changeover instructions for switching between
refrigerant types. Protect yourself and your equipment by
following all manufacturer guidelines.
Also, ensure that your refrigeration hoses are
specified for use with R-134a refrigerant. Research has
shown that compounds in standard refrigeration hoses may
enter sealed systems and ultimately
in an R-134a system.
R-134a refrigeration systems
The sealed refrigeration system will consist of the
same basic components being utilized in the R-12 systems.
There is a 10% to 15% discharge pressure increase
using R-134a, with a 5% to 10% decrease in suction
pressure when compared to the same product with an R-
12 system operating at 90°F (32°C) ambient
ture conditions. Lower suction pressures result from the
lower density of R-134a refrigerant which effects refriger-
ant flow rate. R-134a systems commonly operate in a 1"-
2" vacuum on the suction side.
Products using R-134a refrigerant will generally
have a longer capillary tube to maintain a similar flow rate
and some models will have a larger condenser to reduce
the discharge pressures and lower start-up sound transmis-
sion.
Miscibility of r-134a and ester oil
A special synthetic oil known as Ester oil is used as
a lubricant in refrigeration systems operating on R-134a.
Ester oils are produced from alcohols and fatty acids
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oils have a pleasant aroma reminiscent of fruit.
additives for improving certain properties such as
viscosity, temperature sensitivity, etc. These additives are
often aggressive, and skin contact with Ester oils should
therefore be avoided.
refrigerant system is that the oil mix with the refrigerant.
Since mineral oil and ordinary synthetic oil DO NOT mix
with R-134a, Ester oil is used for lubrication. Ester oil
dissolves in R-134a.
used with R-12 (R-12 contains chlorine) or any other
compound containing chlorine. Therefore, R-134a
refrigeration systems have virtually no tolerance for
restrict the cap tube
chlorine molecules from CFC refrigerants (R-134a is an
HFC and contains no chlorine).
CAUTION: During R-134a service, it is
extremely important to avoid using
equipment that may contain residual amounts
of mineral oil, CFC's or HCFC's which could
enter and contaminate the sealed system.
tempera-
system operating on R-12 may contain small quantities of
mineral oil which can block the capillary tube in a system
operating on R-134a. As little as one milligram may be
sufficient to cause a blockage. In addition, sealed system
components that have been used with CFC systems must
not be used with R-134a systems. These components may
contain residual amounts of refrigerant and oil which
could damage an R-134a system.
134a, tests were carried out on a different type of synthetic
oil known as Poly-Alkaline Glycol (PAG). This oil is also
used in certain air conditioning systems for cars. PAG and
Ester oil DO NOT mix with one another. Service equip-
ment used for R-134a / Ester oil must not come into
contact with PAG.
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and are available in several different variants. Ester
Ester oils generally include various types of
One of the most important requirements made on a
Ester oil is broken down by chlorine and cannot be
For example, hoses that were used for a refrigeration
At the earliest stage of development work on R-