Lenox XC14 Air Conditioner User Manual


 
Page 27
XC14 SERIES
START: Measure outdoor ambient temperature
NOTE − Do not attempt to charge system where a
dash appears, system could be overcharged.
Superheat is taken at suction line service port.
Suction line superheat must never be less than 5ºF
at the suction line service port.
USE WEIGH-IN METHOD
Weigh-in or remove refrigerant
based upon line length
SHº (Superheat) Values (+/−5ºF)
Wet Bulb (air entering indoor coil)
ºF* 50 52 54 56 58 60 62 64 66 68 70 72 74 76
40 15 18 20 23 26 29 32 34 38 41 43 46 48 51
45 13 16 18 21 24 27 30 33 36 39 41 44 46 49
50 11 14 16 19 22 25 28 31 34 37 39 42 44 47
55 9 12141720232730333638404244
60 7 10121518212427303335384043
65 - 6 10 13 16 19 21 24 27 30 33 36 38 41
70 - - 7 1013161921242730333639
75 - - - 6 9 121518212428313437
80 - - - - 5 8 12 15 18 21 25 28 31 35
85 - - - - - - 8 11 15 19 22 26 30 33
90 - - - - - - 5 9 131620242731
95 - - - - - - - 6 101418222529
100 --------81216212428
105 --------5913172226
110 ---------611152025
115 ----------8141824
* Dry−bulb temperature (ºF) of entering outdoor ambient air.
1. Confirm proper airflow across coil using figure 20.
2. Compare unit pressures with table 4, Normal
Operating Pressures.
3. Use SUPERHEAT to correctly charge unit or to
verify the charge is correct.
4. Set thermostat to call for heat (must have a cooling
load between 70-80ºF (21−26ºC)
5. Connect gauge set.
6. When heat demand is satisfied, set thermostat to
call for cooling.
7. Allow temperatures and pressures to stabilize.
8. Measure the suction line pressure and use the use
value to determine saturation temperature (table
3):
SATº =_________
9. Record suction line temperature:
VAPº =_________
10. Subtract to determine superheat (SHº):
VAPº − _____ SATº ______ = SHº______
11. Record the wet bulb temperature (air entering
indoor coil):
WB =_______
12. Record outdoor ambient temperature.
13. Compare results with table to the left.
If value is MORE
than shown, then
ADD refrigerant.
If value is LESS than
shown, then REMOVE
refrigerant.
If refrigerant is
REMOVED, retest to
confirm that unit is
properly charged.
MORE or
LESS
If refrigerant is
ADDED, retest to
confirm that unit is
properly charged.
ABOVE or
BELOW
39ºF and
BELOW
40ºF
and
ABOVE
Figure 24. Using HFC−410A Superheat (Fixed Orifice) Charge Method
Table 3. HFC−410A Temperature (°F) − Pressure (Psig)
°F Psig °F Psig °F Psig °F Psig °F Psig °F Psig °F Psig °F Psig
32 100.8 48 137.1 63 178.5 79 231.6 94 290.8 110 365.0
125 445.9
141 545.6
33 102.9 49 139.6 64 181.6 80 235.3 95 295.1 111 370.0 126 451.8 142 552.3
34 105.0 50 142.2 65 184.3 81 239.0 96 299.4 112 375.1 127 457.6 143 559.1
35 107.1 51 144.8 66 187.7 82 242.7 97 303.8 113 380.2 128 463.5 144 565.9
36 109.2 52 147.4 67 190.9 83 246.5 98 308.2 114 385.4 129 469.5 145 572.8
37 111.4 53 150.1 68 194.1 84 250.3 99 312.7 115 390.7 130 475.6 146 579.8
38 113.6 54 152.8 69 197.3 85 254.1 100 317.2 116 396.0 131 481.6 147 586.8
39 115.8 55 155.5 70 200.6 86 258.0 101 321.8 117 401.3 132 487.8 148 593.8
40 118.0 56 158.2 71 203.9 87 262.0 102 326.4 118 406.7 133 494.0 149 601.0
41 120.3 57 161.0 72 207.2 88 266.0 103 331.0 119 412.2 134 500.2 150 608.1
42 122.6 58 163.9 73 210.6 89 270.0 104 335.7 120 417.7 135 506.5 151 615.4
43 125.0 59 166.7 74 214.0 90 274.1 105 340.5 121 423.2 136 512.9 152 622.7
44 127.3 60 169.6 75 217.4 91 278.2 106 345.3 122 428.8 137 519.3 153 630.1
45 129.7 61 172.6 76 220.9 92 282.3 107 350.1 123 434.5 138 525.8 154 637.5
46 132.2 62 175.4 77 224.4 93 286.5 108 355.0 124 440.2 139 532.4 155 645.0
47 134.6 78 228.0 109 360.0 140 539.0