30Hxa System Charge For Start-Up; To Charge The 30Hxa Systems; 30Hxa Units - Carrier 30HXA Installation Instructions Manual

30HXC UNITS — The 30HXC units are shipped from the
factory with a full charge of R-134a. Unit should not need
to be charged at installation unless a leak was detected in
Step 6 — Leak Test Unit section on page 26. If dehydration
and recharging is necessary, use industry standard practices
or refer to Carrier Standard Services Techniques Manual as
required.
30HXA UNITS — The 30HXA units are shipped with a hold-
ing charge of R-134a. The complete charge for the 30HXA,
the remote condenser(s), and interconnecting piping must be
field supplied.

To charge the 30HXA systems:

1. Add liquid charge into the cooler using the
type fitting located on the tube going into the bottom
of the cooler. This fitting is located between the elec-
tronic expansion valve (EXV) (076-146 units) or the
economizer (161-186 units) and the cooler. Add approxi-
mately 2 lb/nominal ton (0.9 kg/nominal kW). This amount
of charge should be sufficient to allow the unit to start.
The approximate system charges are shown in Table 6.
2. Raise the compressor discharge to approximately 125 F
(51.7 C) saturated discharge temperature (185 psig
[1276 kPa]) by throttling the condenser air (or water) in-
take. Add charge until there is approximately 18 to 20 F
(10.0 to 11.1 C) of system subcooling (saturated dis-
charge temperature − actual temperature entering the EXV).
3. Check for a clear sight glass. If the unit is not fully loaded,
⁄ -in. Schrader-
1
4
27
NOTE: On the units equipped with economizers
(30HXA161-186), the EXV is located inside the econo-
mizer so the temperature must be measured entering the
economizer (tube entering bottom of economizer).
the sight glass might be flashing. This is normal for a
partially-loaded unit.
Table 6 — 30HXA System Charge for
Start-Up
CIRCUIT A
UNIT
CHARGE
30HXA
Lb Kg
076 75 34.0
086 94 42.6
096 114 51.7
106 134 60.8
116 137 62.1
126 137 62.1
136 147 66.7
146 161 73.0
161 190 86.2
171 154 69.9
186 186 84.4
CIRCUIT B
CHARGE
Lb Kg
75 34.0
80 36.3
80 36.3
80 36.3
95 43.1
116 52.6
125 56.7
132 59.9
132 59.9
186 84.4
186 84.4