Installation and Maintenance Manual

Installation Mechanical
30 RTAE-SVX001B-EN
Low Evaporator Refrigerant Cutout, Glycol Requirements
The table below shows the low evaporator temperature
cutout for different glycol levels. Additional glycol beyond
the recommendations will adversely effect unit
performance.The unit efficiency will be reduced and the
saturated evaporator temperature will be reduced. For
some operating conditions this effect can be significant.
If additional glycol is used, then use the actual percent
glycol to establish the low refrigerant cutout setpoint.
Note: Table below is not a substitute for full unit
simulation for proper prediction of unit
performance for specific operating conditions. For
information on specific conditions, contactTrane
product support.
Table 16. Low evaporator refrigerant temperature cutout (LERTC) and low water temperature cutout (LWTC)
Ethylene Glycol Propylene Glycol
Glycol
Percentage
(%)
Solution
Freeze Point
(°F)
Minimum
Recommended
LERTC (°F)
Minimum
Recommended
LWTC (°F)
Glycol
Percentage
(%)
Solution
Freeze Point
(°F)
Minimum
Recommended
LERTC (°F)
Minimum
Recommended
LWTC (°F)
0 32.0 28.6 35.0 0 32.0 28.6 35.0
2 31.0 27.6 34.0 2 31.0 27.6 34.0
4 29.7 26.3 32.7 4 29.9 26.5 32.9
5 29.0 25.6 32.0 5 29.3 25.9 32.3
6 28.3 24.9 31.3 6 28.7 25.3 31.7
8 26.9 23.5 29.9 8 27.6 24.2 30.6
10 25.5 22.1 28.5 10 26.4 23.0 29.4
12 23.9 20.5 26.9 12 25.1 21.7 28.1
14 22.3 18.9 25.3 14 23.8 20.4 26.8
15 21.5 18.1 24.5 15 23.1 19.7 26.1
16 20.6 17.2 23.6 16 22.4 19.0 25.4
18 18.7 15.3 21.7 18 20.9 17.5 23.9
20 16.8 13.4 19.8 20 19.3 15.9 22.3
22 14.7 11.3 17.7 22 17.6 14.2 20.6
24 12.5 9.1 15.5 24 15.7 12.3 18.7
25 11.4 8.0 14.4 25 14.8 11.4 17.8
26 10.2 6.8 13.2 26 13.8 10.4 16.8
28 7.7 4.3 10.7 28 11.6 8.2 14.6
30 5.1 1.7 8.1 30 9.3 5.9 12.3
32 2.3 -1.1 5.3 32 6.8 3.4 9.8
34 -0.7 -4.1 5.0 34 4.1 0.7 7.1
35 -2.3 -5.0 5.0 35 2.7 -0.7 5.7
36 -3.9 -5.0 5.0 36 1.3 -2.1 5.0
38 -7.3 -5.0 5.0 38 -1.8 -5.0 5.0
40 -10.8 -5.0 5.0 40 -5.2 -5.0 5.0
42 -14.6 -5.0 5.0 42 -8.8 -5.0 5.0
44 -18.6 -5.0 5.0 44 -12.6 -5.0 5.0
45 -20.7 -5.0 5.0 45 -14.6 -5.0 5.0
46 -22.9 -5.0 5.0 46 -16.7 -5.0 5.0
48 -27.3 -5.0 5.0 48 -21.1 -5.0 5.0
50 -32.1 -5.0 5.0 50 -25.8 -5.0 5.0