Installation manual

IM-487 Page 27
into the condenser. Approximately 75% of the total require-
ment estimated for the unit can be charged in this manner.
4. After 75% of the required charge has entered the con-
denser, reconnect the refrigerant drum and charging line
to the suction side of the system. Again purge the connect-
ing line, stand the drum with the connection side up, and
place the service valve in the open position.
Important: At this point, interrupt the charging procedure
and do prestart checks before attempting to com-
plete the refrigerant charge.
Note: Stamp the total operating charge on the unit name-
plate for future reference.
Refrigerant Charge
Factory installed DX coils are designed to use R-22. The
total system charge is the sum of these three values:
1. Condensing unit charge. Refer to manufacturer’s data.
2. Evaporator coil charge. Refer to Table 7 and Table 8.
3. Charge for the length of interconnecting piping installed
by field. Refer to Table 9.
Note: Factory installed DX coils are intended for one
refrigerant circuit on unit size 800 and two refriger-
ant circuits containing identical weights of refriger-
ant on all other sizes. The values shown in Table 7,
Table 8 and Table 9 are for each circuit.
Note: The total operating charge per circuit should not
exceed the pumpdown capacity per circuit, specified
by the condensing unit manufacturer.
Table 7: Approximate DX Coil Refrigerant Charge Per Circuit
Table 8: Approximate Refrigerant Charge Per Circuit
* The RDS 802C unit has two refrigerant circuits
Table 9: Weight of refrigerant R-22 in copper lines (pounds per 100 feet of Type L tubing)
Unit Size
DX Coil R-22 Charge (Lbs./Circuit)
Flat Coil Staggered Coil
047C 3 x No. of DX Rows 3.5 x No. of DX Rows
077C 5 x No. of DX Rows 6.5 x No. of DX Rows
Unit Size Evaporator Coil (Lbs/Ckt/Coil Row)
802 3.30
802C* 2.45
O.D. Line Size
VOL. Per 100 FT.
In Cubic Feet
Weight of Refrigerant, Lbs./100 Feet
Liquid @100°F
Hot Gas
@120°F Cond.
Suction Gas (Superheat to 85°F)
30°F
40°F
3/8" 0.054 3.84 0.202 0.052 0.077
1/2" 0.100 7.12 0.374 0.098 0.143
5/8" 0.162 7.12 0.605 0.158 0.232
7/8" 0.336 24.00 1.260 0.323 0.480
1-1/8" 0.573 40.80 2.140 0.550 0.820
1-3/8" 0.872 62.10 3.260 0.839 1.250
1-5/8" 1.237 88.00 4.620 1.190 1.770
2-1/8" 2.147 153.00 8.040 2.060 3.060
2-5/8" 3.312 236.00 12,400 3.180 4.720
3-1/8" 4.728 336.00 17.700 4.550 6.750
3-5/8” 6.398 456.00 24.000 6.150 9.140
4-1/8" 8.313 592.00 31.100 8.000 11.190