Electrolux European Wine Tower, Руководство по обслуживанию

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34
D - Refrigeration System
Leak Detection
R-134a system leaks can be pinpointed by means
of an electronic leak detector or by bubble solution.
Electronic leak detectors for R-134a service are
currently available from several manufacturers. The
least expensive models are non-selective detectors
that will detect any type of emission or vapor
present, regardless of its chemical composition.
Some non-selective detectors designed for use
with R-12 may have a much lower sensitivity
when used with R-134a. However, newly designed
detectors with good R-134a sensitivity are now
available. Be sure to consult with the manufacturer
before selecting or using a non-selective detector
with R-134a.
Halogen-specific detectors use a specialized
sensor that allows detection of compounds
containing chlorine, fluorine, bromine, and iodine
without being activiated by other species. The
REFRIGERANTS
R-12 R-134a
NAME
Dichlorodifluoro-
methane
1,1,1,2--Tetra-
fluoromethane
Formula
CCI
2
F
2
CH
2
F-CF
3
Molecular Weight (g/mol)
120.93 102.3
Ozone Depletion Potential
(ODP)
1 0
Global Warming Potential
(GWP)
3.1 0.3
Boiling Point °F
-21.6 -15.7
Vapor Pressure (77°F) 80 psig 82 psig
Flammability None None
Solubility of Water in
Refrigerant (wt% @ 77°F)
0.009 0.11
Halogen-specific detectors use a specialized
sensor that allows detection of compounds
containing chlorine, fluorine, bromine, and iodine
without being activiated by other species. The
major advantage of this type of detector is a
reduction in the number of “nuisance alarms”.
Halogen-specific detectors are generally more
expensive than non-selective detectors but feature
higher sensitivity.
R-134a properties
The properties of R-134a are very similar to those
of R12. The principal data for the two refrigerants
are shown in the chart below.
major advantage of this type of detector is a
reduction in the number of “nuisance alarms”.
Halogen-specific detectors are generally more
expensive than non-selective detectors but feature
higher sensitivity.