Refrigerant Charge; No Charge; Low Charge Cooling; To Use Cooling Charging Charts - Carrier INFINITY 48XL-A Installation Instructions Manual

HEATING INPUT (BTU/HR)*
High Stage Low Stage
40,000 26,000
60,000 39,000
90,000 58,500
115,000 75,000
130,000 84,500
*Cubic ft of natural gas per hour for gas pressures of .5 psig (14 IN. W.C.) or less and a pressure drop of .5 IN. W.C. (based on a .60 specific gravity gas). Ref:
Table 6.2 (b) NPFA 54 / ANSI Z223.1 ---2009.
UNIT
SIZE
600 700 800
24 0.005 0.007 0.010
30 – 0.007 0.010
36 – – –
42 – – –
48 – – –
60 – – –
FILTER SIZE
in. (mm)
500 600 700
20X20X1
0.05 0.07 0.08
(508x508x25)
24X30X1
— — —
(610x762x25)
24X36X1
— — —
(610x914x25)
IMPORTANT: When evaluating the refrigerant charge, an
indicated adjustment to the specified factory charge must always be
very minimal. If a substantial adjustment is indicated, an abnormal
condition exists somewhere in the cooling system, such as
insufficient airflow across either coil or both coils.

REFRIGERANT CHARGE

The amount of refrigerant charge is listed on the unit rating plate
and/or the physical data table. Refer to the Refrigeration Service
Techniques Manual, Refrigerants Section.

NO CHARGE

Check for leak. Use standard evacuating techniques. After
evacuating system, weigh in the specified amount of refrigerant
(refer to system rating plate).

LOW CHARGE COOLING

Use Cooling Charging Chart (Fig. 23). Vary refrigerant until the
conditions of the chart are met. Note that charging charts are
different from type normally used. Charts are based on charging
the units to correct subcooling for the various operating conditions.
Accurate pressure gauge and temperature sensing devices are
required. Connect the pressure gauge to the service port on the
suction line. Mount the temperature sensing device on the suction
line and insulate it so that the outdoor ambient does not affect the
reading. Indoor air CFM must be within the normal operating
range of the unit.
Table 6 – Heating
GAS SUPPLY PRESSURE (IN. W.C.)
NUMBER OF NUMBER OF
ORIFICES ORIFICES
2
3
3
3
3
Table 7 – ECM Wet Coil Pressure Drop (IN. W.C.)
STANDARD CFM (SCFM)
900 1000 1100 1200
0.012 0.015 – –
0.012 0.015 0.018 0.021
0.019 0.023 0.027 0.032
– 0.014 0.017 0.020
– – – 0.027
– – – –
Table 8 – Filter Pressure Drop Table (IN. W.C.)
800 900 1000 1100 1200
0.1 0.12 0.13 0.14 0.15
— 0.05 0.6 0.07 0.07
— — — — 0.06
Inputs
Natural
Min Max
4.0 13.0
4.0 13.0
4.0 13.0
4.0 13.0
4.0 13.0
1300 1400 1500 1600
– – – –
0.024 – – –
0.037 0.042 0.047 –
0.024 0.027 0.031 0.035
0.032 0.036 0.041 0.046
– – 0.029 0.032
CFM
1300 1400 1500 1600 1700
— — — — —
0.08 0.09 0.1 — —
0.07 0.07 0.08 0.09 0.09

TO USE COOLING CHARGING CHARTS

Take the liquid line temperature and read the manifold pressure
gauges.
Refer to the chart to determine what the liquid line temperature
should be.
NOTE:
If the problem causing the inaccurate readings is a
refrigerant leak, refer to Check for Refrigerant Leaks section.
NON- -COMMUNICATING
HEATING MODE: 4- -WIRE THERMOSTAT
This mode of operation is provided only in the case where the UI
has failed or is otherwise unavailable. If communications cannot be
established with the UI, the Infinity furnace board will enable the
standard thermostat input terminals to allow simple thermostatic
control of the 48XL unit.
For control with a standard thermostat, disconnect the ABCD
connectors from both control boards and using No. 18 AWG
color- -coded, insulated type 90°C minimum or equivalent wire,
make the connections between the standard thermostat, the furnace
board, and the HP/AC board per Fig. 22. Recommend the use of
interconnecting wire with 105C, 600V, 2/64" insulation.
The Infinity control will respond to cooling and heating demands
with the maximum safe airflow based on gas furnace output and
unit cooling capacity.
29
MANIFOLD PRESSURE (IN. W.C.)
Natural
High Stage Low Stage
3.2∼ 3.8 1.4 ∼ 2.0
3.2∼ 3.8 1.4 ∼ 2.0
3.2∼ 3.8 1.4 ∼ 2.0
3.2∼ 3.8 1.4 ∼ 2.0
3.2∼ 3.8 1.4 ∼ 2.0
1700 1800 1900 2000
– – – –
– – – –
– – – –
0.039 0.043 – –
0.052 0.057 0.063 0.068
0.036 0.040 0.045 0.049
1800 1900 2000 2100 2200
— — — — —
— — — — —
0.10 0.11 0.12 0.13 0.14
EMERGENCY COOLING
2100
–
–
–
–
–
0.053
2300
—
—
0.14
/