Heat Controller HFC Refrigerant R410a Application & Service Manual page 2

R410a Application and Service Guide
Although the bulk of this manual is information
regarding R410a, R407c will also be discussed for
purposes of comparison and since it is one of the so-
called new refrigerants.
R410a Overview
R410a is a non-chlorine based (HFC) refrigerant, that
with R407c and R134a, is seen as the future of all refrig-
erants used worldwide. R410a characteristics compared
to R22 are:
• Binary and near azeotropic mixture of R32-50%
and R125-50%
• Higher effi ciencies
• Higher operating pressures
• Requires POE oil in compressors
• In some systems can result in smaller heat exchang-
ers with the same performance
• Low global warming potential and zero ozone
depletion (0.39/0.0)
• Temperature glide of 0.2°F
• Containers are "ROSE" colored
R407c Overview
R407a is a non-chlorine based (HFC) refrigerant. R407c
characteristics compared to R22 are:
• Ternary and near azeotropic mixture of R32-23%,
R125-25%, R134a-52%
• Slightly lower effi ciencies
• Nearly equal operating pressures
• Requires POE oil in compressors
• Considered a near drop-in replacement for R22
• Low global warming potential and zero ozone
depletion (0.34/0.0)
• Temperature glide of 10°F
• Containers are "MEDIUM BROWN" colored
What is "Glide"?
Pure compounds like CFC-R12 boil and condense at
exactly the same temperature for a given pressure. Near-
azeotropic blends are not pure compounds but a blend of
compounds. These compounds will have a temperature
glide or range of temperatures in which the blend will
boil or condense. In these situations, for example R407c,
a chart listing a bubble and dew point must be used as the
pressure/temperature chart since it has a glide of 10°F.
The bubble point is used for subcooling calculations.
The dew point is used for superheat calculations. See
Table 1. R410a has a very small glide (0.2°F) and acts
as a single component refrigerant. Therefore R410a can
Page 2
utilize a more traditional table with only one pressure
column as shown in Table 2.
What is "Fractionation"?
Many of the newer refrigerants are a blend of two or more
other refrigerants. At various conditions these compo-
nents can separate and change the ratio of the original
mixture and in effect change the total performance of the
remaining blend. Therefore it is recommended to use the
refrigerant in liquid form, insuring that all of the compo-
nents are handled together in the proper blend.
Table 1. R407c Pressure/Temperature Chart
R407c
T Temperature Temperature Bubble
Pressure
(for subcooling) for (superheat)
°F
-15
-10
-5
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
125
130
135
140
145
150
Dew
Pressure
psig psig
17.2 9.2
21.0 12.3
25.1 15.7
29.5 19.4
34.4 23.4
39.6 27.8
45.2 32.6
51.3 37.8
57.8 43.4
64.8 49.4
72.4 56.0
80.4 63.0
89.0 70.6
98.1 78.7
107.9 87.4
118.2 96.7
129.2 106.6
140.9 117.1
153.2 128.4
166.2 140.4
180.0 153.1
194.6 166.5
209.9 180.8
226.0 195.9
243.0 211.9
260.8 228.7
279.5 246.5
299.0 265.3
319.6 285.0
341.0 305.8
363.4 327.6
386.9 350.5
411.3 374.6
436.8 399.8