Guidelines For The Utilization Of Guidelines For The Utilization Of - Tecumseh Page 3
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4B.
A given displacement compressor with R600a will produce 50 to 60% of the capacity that it would with
R134a. R290 will produce 85 to 90% compared to R404A.
C.
Table 2
shows the comparison of some properties of R600a, R134a, R290, and R404A. The data is
taken at the standard refrigerant conditions of 5°F (-15°C) evaporating and 86°F (+30°C) condensing.
Data
R600a
R134a
R290
R404A
Evaporating pressure PSIA
12.8
23.8
42.3
52.8
(kPa Abs.)
(88.5)
(164.0)
(291.6)
(364.1)
Condensing pressure PSIA
58.6
111.7
156.4
205.8
(kPa Abs.)
(404.5)
(771.0)
(1079)
(1419)
0.1556
0.5173
0.4061
0.9658
Sat. Vap. Density @5°F
(-15°C) Lbs/ft³ (kg/m³)
(2.489)
(8.278)
(6.498)
(18.57)
33.98
74.13
30.24
63.71
Sat. Liq. Density @86°F
(30°C) Lbs/ft³ (kg/m³)
(543.7)
(1186)
(483.9)
(1020)
159.1
90.12
169.7
76.45
Latent Heat @5°F
(-15°C) BTU/ Lb (kJ/kg)
(355.7)
(201.5)
(379.4)
(177.7)
Table 2: Comparison of some properties of R600a, R134a, R290 and R404A
D.
R600a and R290 are compatible with all materials used in Tecumseh Products’ hermetic compressors
and condensing units that are designated for use with these refrigerants.
II.
LUBRICANTS
A.
R600a and R290 are miscible with and soluble in conventional mineral and synthetic oils used with
HCFC’s.
III.
SYSTEM DESIGN
A.
Compressor selection: Tecumseh offers selected compressors for use with R600a and R290. These
compressors have the letter “M” as the designator for R600a and the letter “U” as the designator for
R290, e.g., AZ_1335M_and AE_9415U_. It will be necessary to test each compressor selection in
the applications to determine its suitability, since system operating conditions vary greatly from one
application to another.
B.
Capillary tube selection:
In general, capillary tubes selected for R134a applications should be adequate
as a preliminary selection for R600a. Likewise, capillary tubes selected for R404A applications should
be adequate as a preliminary selection for R290. As with any capillary tube selection, system testing
is necessary to determine the proper final selection.
C.
Expansion valve selection: The expansion valve manufacturers have designed product specifically for
use with R600a and R290. Consult them for their recommendations.
D.
Driers: R600a and R290 will use the same driers as HCFC’s.
E.
Return gas/ discharge temperatures: The theoretical discharge temperature for R600a is lower than
that of R134a at similar conditions. R290 theoretical discharge temperature is about the same as
R404A. Therefore, existing compressor guidelines regarding return gas and discharge temperatures
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