System Charging; R407C/R410A Refrigerant; Estimating Refrigerant Charge - Trane TR-SCS Series Installation, Operation And Maintenance Manual

System Charging

Refrigerant charging pressures vary depending on the
type of refrigerant used in the unit. Before charging, check
the unit nameplate to confirm the type of refrigerant to
use. Table 1 and Table 2
characteristics for R407C and R410A.

R407C/R410A Refrigerant

R407C and R410A are blended refrigerants recognized for
being safer for the environment. These refrigerants
contain no chlorine, the component in HCFC's that
destroys the earth's ozone layer. However, the same care
should be taken to prevent leakage because R407C and
R410A can contribute to the greenhouse effect if released.
If the refrigerant gas is released in an enclosed space, it
can suffocate.
Refrigerants that are multi-component blends have
component parts with different volatilities that result in a
change in composition and saturation temperature as
evaporation and condensation occur. Typically, the
composition of R407C vapor is different than that of R407C
Table 5. TR-SCS condenser refrigerant charge weights (lb)
TR-SCS Model Number
012-S
018-S
024-S
036-S
060-S
060-D*
096-S
096-D*
120-S
120-D*
144-S
144-D*
192-S
192-D*
252-S
252-D*
276-D*
312-D*
447-D*
525-D*
597-D*
683-D*
940-D*
1366-D*
SS-SVX006C-EN
show the temperature/pressure
R407C Charge
-20°F Ambient and
Higher
0.6
0.6
1.3
1.9
2.8
2.8
3.6
3.6
5.4
5.4
7.2
7.2
8.2
8.2
8.2
8.2
12.4
12.4
16.5
18.4
18.4
24.6
32.6
49.1
liquid within a contained system. The composition of
liquid R407C refrigerant remains relatively constant,
however, the refrigerant vapor tends to separate into its
component parts even when circulating.

Estimating Refrigerant Charge

When charging a system with R407C or R410A refrigerant
it will be necessary to weigh in the refrigerant. Calculate
the amount of refrigerant needed by adding the amount of
refrigerant required for the A/C unit (shown in the A/C unit
IOM provided separately) plus the refrigerant for the
condenser (Table 5
piping (Table 7).
Table 5 and Table 6
amount of R407C or R410A refrigerant needed to charge
TR-SCS or TR-SCS-MC condensers by model number. In
cases of dual circuited condensers, divide the total weight
(lb) shown by 2 to determine the amount of refrigerant
needed for each circuit. The values shown in Table 5 and
Table 6 are conservative for the purpose of preventing the
system from being overcharged.
R407C Charge
(Condenser with
Receiver)
-30°F Ambient -20°F Ambient & Higher
2.7
2.7
5.4
8.1
12.2
12.2
15.7
15.7
23.6
23.6
31.4
31.4
35.9
35.9
35.9
35.9
53.8
53.8
71.8
80.1
80.1
106.9
141.9
213.7
and Table 6) plus the refrigerant
may be used to estimate the minimum
R410A Charge
R410A Charge (Condenser with
-30°F Ambient
0.5
0.5
1.0
1.5
2.2
2.2
2.8
2.8
4.2
4.2
5.6
5.6
6.4
6.4
6.4
6.4
9.7
9.7
12.9
14.4
14.4
19.2
25.5
38.4
Installation
Receiver)
2.6
2.6
5.2
7.8
11.7
11.7
15.1
15.1
22.7
22.7
30.2
30.2
34.5
34.5
34.5
34.5
51.7
51.7
69.0
77.0
77.0
102.8
136.5
205.6
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