Lennox XP21 Series - Page 91

HFC-410A CHARGING INFORMATION
FOR COMPLETE CHARGING DETAILS, REFER TO THE OUTDOOR UNIT INSTALLATION INSTRUCTION.
Maintenance checks using the Normal Operating Pressures table
Table 1 may be used to help perform maintenance checks. This table is not a procedure for charging the system
and any minor variations in the pressures may be expected due to differences in installations. However,
significant deviations could mean that the system is not properly charged or that a problem exists with some
component in the system. The values in Table 2 are “most-popular-match-up” pressures; indoor match up,
indoor air quantity, and indoor load will cause the pressures to vary.
Match-ups/Charge Levels and Line Set Lengths
Table 2 lists all the Lennox recommended indoor unit match-ups along with the charge levels for the various
sizes of outdoor units. Charge levels on the unit nameplate are based on installations with 15' (4.6m) line
sets; be sure to consider any difference in line set length (see Installation Instructions for more
details).
Charge Using the Weigh‐in Method
If the system is void of refrigerant, locate and repair any leaks and then weigh in the refrigerant charge into
the unit. For charge adjustments, be sure to consider line set length differences and, referring to table 2, adjust
for the matchup difference.
1 - Weigh in the unit nameplate charge, adjusting for matchup and line set length differences. If weighing
facilities are not available use the Subcooling method.
2 - Conduct leak check; evacuate as previously outlined.
3 - Recover the refrigerant from the unit.
Charge Using the Subcooling Method
Cooling Mode—When the outdoor ambient temperature is 60°F (15°C) and above, use the cooling mode
to adjust the charge using the subcooling method. Target subcooling values in table 2 are based on 70 to 80°F
(21-27°C) indoor return air temperature.
Heating Mode—When the outdoor ambient temperature is below 60°F (15°C), use the heating mode to
adjust the charge using the subcooling charge levels (table ). Target subcooling values in table 2 are based
on 65-75°F (18-24°C) indoor return air temperature.
Table 1 - Normal Operating Pressures (Liquid +10 and Suction +5 psig)
*Temperature of the air entering
the outdoor coil.
-024 -036 -048 -060
5F (5C)* Liq Vap Liq Vap Liq Vap Liq Vap
Low Stage
Heating
Operation
40 (4) 319 104 369 91 367 92 353 91
50 (10) 345 122 331 117 385 113 352 115
Low Stage
Cooling
Operation
65 (18) 224 149 224 145 229 142 227 139
75 (24) 260 150 261 148 266 143 263 142
85 (29) 303 151 303 150 311 145 305 144
95 (35) 348 154 350 152 358 147 352 147
105 (41) 397 156 400 154 410 150 402 150
115 (46) 453 155 456 157 468 152 458 153
High Stage
Heating
Operation
20 (-7) 312 67 293 62 326 63 305 62
30 (-1) 351 82 309 76 353 76 320 72
40 (4) 364 98 322 90 375 93 347 90
50 (10) 390 117 341 109 405 110 366 105
High Stage
Cooling
Operation
65 (18) 231 144 237 140 240 138 236 134
75 (24) 270 146 275 142 279 140 272 136
85 (29) 312 148 315 146 323 142 316 139
95 (35) 360 150 363 148 371 144 364 141
105 (41) 411 152 415 151 423 146 416 144
115 (46) 467 154 473 153 481 149 475 146
Table 2 - Indoor Units Matchups and Subcooling Charge Levels
INDOOR HEAT
MATCHUP PUMP
Target
Subcooling
HeatCool
(+
5ºF) (+1ºF)
*Add charge
INDOOR HEAT
MATCHUP PUMP
Target
Subcooling
HeatingCooling
(+
5ºF) (+1ºF)
*Add charge
XP21-024
lb oz
XP21-048
lb oz
CB(X)27UH-024 15 4 0 0 CB(X)27UH-048 24 4 1 0
CB(X)27UH-030 22 7 1 10 CB(X)27UH-060 14 4 1 6
CBX32MV-036 and CBX32M-036 22 7 1 10 CBX32MV-048 and CBX32M-048 24 4 1 0
CBX32MV-24/30 and CBX32M-030 15 4 0 0 CBX32MV-060 and CBX32M-060 21 4 1 14
CBX40UHV-024 22 7 1 10 CBX32MV-068 14 4 1 0
CBX40UHV-030 22 7 1 10 CBX40UHV-048 24 4 1 0
CBX40UHV-036 22 7 1 10 CBX40UHV-060 21 4 1 14
CH23-51 18 4 0 10 CH23-68 14 4 1 6
CH33-31 18 4 0 10 CH33-49C 21 4 1 14
CH33-42 18 4 0 10 CH33-50/60C 21 4 1 14
CR33-48 28 4 0 0 CH33-62D 20 4 1 7
CX34-31 27 4 0 10 CR33-50/60 32 4 0 0
CX34-44/48B 22 5 1 3 CR33-60D 32 4 0 0
CX34-38 25 6 1 7 CX34-49 21 5 0 10
XP21-036
lb oz CX34-62C 11 4 1 5
CB(X)27UH-036 17 5 0 0 CX34-62D 11 4 1 5
CB(X)27UH-042 12 5 1 10
CBX32MV-036 and CBX32M-036 17 5 0 0
CBX32MV-048 and CBX32M-048 12 5 1 10
XP21-060
lb oz
CBX40UHV-036 17 5 0 0 CB(X)27UH-060 7 6 0 10
CBX40UHV-042 12 5 1 10 CBX32MV-060 and CBX32M-060 10 4 0 0
CBX40UHV-048 12 5 1 10 CBX32MV-068 9 4 0 10
CH23-51 19 7 0 0 CBX40UHV-060 10 4 0 0
CH33-43 11 5 0 7 CH23-68 10 4 0 10
CH33-44/48B 11 5 0 7 CH33-49C 7 5 0 0
CH33-48C 11 5 0 7 CH33-50/60C 7 5 0 0
CH33-50/60C 12 7 1 6 CH33-62D 9 4 0 7
CR33-48 28 4 0 0 CR33-50/60 22 5 0 4
CX34-38 15 5 0 7 CR33-60D 22 5 0 4
CX34-44/48B 19 4 0 10 CX34-49 10 5 0 0
CX34-49 10 10 1 10 CX34-62C 7 5 0 0
CX34-50/60C 11 5 0 7 CX34-62D 7 5 0 0
*Amount of charge required in additional to charge shown on unit nameplate. (Remember to consider line set length difference.)
*2P0610* *P580318-01*
06/10 580318-01