Trane 4TWR4 Installation And Operation Manual page 14

Special subcooling applications
Outdoor Unit Model No.
4TWR4017N1
4TWR4018N1
4A6H4018N1
4TWX5018N1
4TWR4024N1
4A6H4024N1
4TWX5024N1
4TWR4030N1
STEP 3 - Stabilize the system by operating for a minimum of 20 minutes.
At startup, or whenever charge is removed or added, the system must be operated for a minimum of 20 minutes to
stabilize before accurate measurements can be made.
STEP 4 - Measure the liquid line temperature and pressure at the outdoor unit's service valve.
Measured Liquid Line Temp = __________ º F
Liquid Gage Pressure = __________ PSIG
Final Subcooling Value = __________ º F
STEP 5 - Use the final subcooling value, refrigerant temperature and pressure from STEP 4, to determine the
proper liquid gage pressure using Table 14.2.
Example: Assume a 12º F Final Subcooling value and liquid temp of 90º F.
1. Locate 12º F Final Subcooling in Table 14.2.
2. Locate the Liquid Temperarature (90º F) in the left column.
3. The Liquid Gage Pressure should be approximately 327 PSIG. (This is the shown as the intersection of the
Final Subcooling column and the Liquid Temperature row.)
STEP 6 - Adjust refrigerant level to attain proper gage pressure.
Add refrigerant if the Liquid Gage Pressure is lower than the chart value.
1. Connect gages to refrigerant bottle and unit as illustrated.
2. Purge all hoses.
3. Open bottle.
4. Stop adding refrigerant when liquid line temperature and Liquid Gage Pressure matches the charging chart
Final Subcooling value.
Recover refrigerant if the Liquid Gage Pressure is higher than the chart value.
14
Indoor Unit Model No.
GAM5A0B18M11
TAM7A0A24H21
TEM6A0C36H31
TEM6A0C36H31
TEM6A0B24H21
107 °F
Subcooling
14 Degrees
13 Degrees
13 Degrees
14 Degrees
Table 14.2
R-410A REFRIGERANT CHARGING CHART
FINAL SUBCOOLING (
LIQUID
8 9 10 11 12
TEMP
( ° F)
LIQUID GAGE PRESSURE (PSI)
55 179 182 185 188 191 195 198
60 195 198 201 204 208 211 215
65 211 215 218 222 225 229 232
70 229 232 236 240 243 247 251
75 247 251 255 259 263 267 271
80 267 271 275 279 283 287 291
85 287 291 296 300 304 309 313
90 309 313 318 322 327 331 336
95 331 336 341 346 351 355 360
100 355 360 365 370 376 381 386
105 381 386 391 396 402 407 413
110 407 413 418 424 429 435 441
115 435 441 446 452 458 464 470
120 464 470 476 482 488 495 501
125 495 501 507 514 520 527 533
From Dwg. D154557P01 Rev. 3
°
F)
13 14
18-BC95D1-5E-EN