Danfoss Performer SH090, Выбор и руководство по применению

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A
PPLICATION GUIDELINES
24 FRCC.PC.007.B5.02
O
PERATING CONDITIONS
The scroll compressor application range is infl u-
enced by several parameters which need to be
monitored for a safe and reliable operation.
These parameters and the main recommenda-
tions for good practice and safety devices are ex-
plained hereunder.
Refrigerant and lubricants •
Motor supply •
Compressor ambient temperature •
Application envelope • (evaporating tem-
perature, condensing temperature, return gas
temperature)
General information
Refrigerant and lubricants
When choosing a refrigerant, diff erent aspects
must be taken into consideration:
• Legislation (now and in the future)
• Safety
• Application envelope in relation to expected
running conditions
• Compressor capacity and effi ciency
• Compressor manufacturer recommendations &
Guidelines
Additional points could infl uence the fi nal
choice:
• Environmental considerations
• Standardisation of refrigerants and lubricants
• Refrigerant cost
• Refrigerant availability
SH compressors are to be used with R410A refrig-
erant, with polyolester oil.
R410A’s superior thermodynamical properties •
compared to R22 and R407C refrigerants allow
for today’s massive – and necessary – switch to
high effi ciency systems.
Zero Ozone Depletion Potential (ODP): R410A •
doesn’t harm the ozone layer.
Global warming potential (GWP): R410A shows •
a relatively high warming potential. However,
the GWP index denotes direct warming eff ect,
which is relevant only in case of release to the at-
mosphere. A more accurate index is T.E.W.I., for
Total Equivalent Warming Impact, which takes
into account indirect contributions due to run-
ning energy costs.
Because of the higher system effi ciency it al- •
lows to achieve, R410A is in this regard the best
refrigerant.
As a near-azeotropic mixture, refrigerant R410A •
behaves like an homogeneous substance,
whereas other zeotropic mixtures such as R407C
and other blends suff er a temperature glide
during phase change that lessens thermal effi -
ciency and makes them diffi cult to transfer from
a container to another.
Reduced refrigerant mass fl ow, permitted by a •
higher heat capacity, induce a lower sound level
of the installation as well as more compact and
lighter systems.
Danfoss Commercial Compressors, along with the
whole refrigeration and air conditioning industry,
shares today’s concern about the environmental
issues that are ozone depletion, global warming
and overall energy consumption. Usual HCFCs
refrigerant fl uids such as R22 are known to be im-
plicated in these harmful phenomena, especially
ozone depletion due to their chlorinated content.
These substances are scheduled to be phased-
out from production and use in coming years,
in accordance with the international Montreal
Protocol (1984).
As a result, new chlorine-free molecules have been
recently developed and are now ready to replace
former fl uids. Among those refrigerants, the HFC
blend R410A is admitted by a great majority of
manufacturers to be the most promising in terms
of environmental impact, stability and effi ciency,
and is already seen as the R22 replacement.
R410A
R
EFRIGERANT
R22 R407C R410A
C
HEMICAL
PROPERTIES
Chlorine content yes no no
Zeotropic pure refrigerant zeotropic mixture near azeotropic mixture
Composition R22 R32/R125/R134a R32/R125
E
NVIRONMENTAL
IMPACT
ODP 0.05 0 0
GWP 1500 1526 1725
T
HERMODYNAMIC
PROPERTIES
Vapour pressure (bar) at 25°C 10.4 11.9 16.5
Cooling capacity of liquid (kJ/kg.K) at 25°C 1.24 1.54 1.84
Cooling capacity of vapor (kJ/kg.K) at 1 atm, 25 °C 0.657 0.829 0.833
Temperature glide (°C) 0 7.4 <0.2