Bryant 582A - Manual (Page 10)

SELECTION PROCEDURE (with example)
I DETERMINE COOLING AND HEATING REQUIRE-
MENTS AT DESIGN CONDITIONS:
Given:
Required Cooling Capacity (TC) . . . . . . . . . . 34,000 Btuh
Btuh Sensible Heat Capacity (SHC) . . . . . . . 25,000 Btuh
Btuh Required Heating Capacity . . . . . . . . . 60,000 Btuh
Condenser Entering Air Temperature . . . . . . . . . . . . 95 F
Indoor-Air Temperature . . . . . . . . . . . 80 F edb 67 F ewb
Evaporator Air Quantity . . . . . . . . . . . . . . . . . . . 1200 cfm
External Static Pressure . . . . . . . . . . . . . . . . . . 0.4 in. wg
Electrical Characteristics . . . . . . . . . . . . . . . . . . 230-1-60
II SELECT UNIT BASED ON REQUIRED COOLING
CAPACITY.
Enter Net Cooling Capacities table at outdoor entering
temperature of 95 F. Unit 582A036 at 1200 cfm and 67 F
ewb (entering wet bulb) will provide a total capacity of
34,400 Btuh and a SHC of 25,400 Btuh.
III SELECT HEATING CAPACITY OF UNIT TO PROVIDE
DESIGN CONDITION REQUIREMENTS.
In the Heating Capacities and Efficiencies table on page 3,
note that the unit 582A036090 will provide 71,910 Btuh
with an input of 90,000 Btuh.
IV DETERMINE FAN SPEED AND POWER REQUIRE-
MENTS AT DESIGN CONDITIONS.
Before entering the air delivery tables, calculate the total
static pressure required. From the given example, the Wet
Coil Pressure Drop Table, and the Filter Pressure Drop
table on page 15, find at 1200 cfm:
External Static Pressure 0.40 in. wg
Wet Coil 0.10 in. wg
Filter/Economizer + 0.12 in. wg
Total Static Pressure 0.62 in. wg
Enter the table for Dry Coil Air Delivery – Horizontal and
downflow Discharge for 230 V and 460 V on page 14. The
fan will deliver 1360 cfm at 0.60 ESP (external static pres-
sure) at high speed and 1167 cfm at 0.60 ESP at medium
speed. The fan speed should be set at high.
V SELECT UNIT THAT CORRESPONDS TO POWER
SOURCE AVAILABLE.
The Electrical Data table on page 21 shows that the unit is
designed to operate at 230-1-60.
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