Trane 4TWR3 Installer's Manual page 6

|nsta||er's Guide
SUBCOOMNG CHARGING iN COOLING ABOVE 55°F OD AMBIENT
The Trane company has always recommended installing
Trane approved matched indoor and outdoor systems.
All Trane split systems are ARI rated with only TXV indoor
systems.
The benefits of installing approved indoor and outdoor split
systems are maximum efficiency, optimum perfbrmance and
the best overall system reliability.
The fbllowing charNng methods are therefore
prescribed fbr systems with indoor TXVs.
1. Subcooling (in the cooling mode) is the on__a!y_l
recommended method of charging above
55°F ambient temperatures.
2. For best results - the indoor temperature
should be kept between 70°F to 80°F. Add
system heat if needed.
3. At start-up, or whenever charge is removed
or added, the system must be operated for a
minimum twenty (20) minutes to stabilize
befbre accurate measurements can be made.
4. Measure Liquid Line Temperature and
Refrigerant Pressure at service valves.
5. Determine total refrigerant line length,
and height (lift) if indoor section is above
the condenser.
6. Determine the Design Subcool Charging
Temperature from the unit nameplate.
7. Locate this value in the appropriate column
of the Subcooling Charging Table. Locate
your liquid line temperature in the left
column of the table, and the intersecting
liquid line pressure under your nameplate
subcool value column. Add refi'igerant to
raise the pressure to match the table, or
LIQUID
TEMP
(°F)
remove refrigerant to lower the pressure. Again, wait
twenty (20) minutes for the system conditions to stabilize
before adjusting charge again.
8. When system is correctly charged, you can refer to
System Pressure Curves (in Service Facts) to verify
typical perfbrmance.
R=410A REFRIGERANT CHARGING CHART
DESIGN SUBCOOLING (°F)
8 I 9 I 10 I 11 ! 12 I la I 14
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. 2
SUBCOOL CHARGING TABLE CORRECTIONS FOR LINE LENGTH AND RISE
_w
Zw
<EL
CC'_
ELW
wZ
rr-7
0 Subtract 10 psig from S.C. Table Pressure
10 20 25 30 40 60
TOTAL REFRIGERANT LINE LENGTH (FEET)
8O
SUBCOOLING CHARGING BELOW 55°F OD AMBIENT - IN HEATING ONLY
1. The Subcool Charging Method in cooling is not recom-
mended below 55°F outdoor ambient.
2. The only recommended method of charging at outdoor
ambients below 55°F, is to weigh in the charge in the
heatin_ mode.
3. Use Nameplate charge plus standard charge adders fbr
line length.
4. Check liquid line temperature and pressure (at the
OD valves) to obtain a minimmn of 10°F subcooling.
5. Add chaige ifa minimum of 10°F subcooling is not obtained
with the nameplate charge plus line length correction.
6. It is important to return in the spring or summer to
accurately charge the system in the cooling mode at
outdoor ambients above 55°F.
6 18-BC51 D1-5