Bryant 604B, Руководство пользователя

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604B CORNER WEIGHTS (IN POUNDS)
I DETERMINE COOLING AND HEATING REQUIREMENTS
AT DESIGN CONDITIONS:
Given:
Required Cooling Capacity (TC) .......................34,500 Btuh
Sensible Heat Capacity (SHC) .........................26,000 Btuh
Required Heating Capacity ...............................36,000 Btuh
Condenser Entering Air Temperature .......................... 95°F
Indoor-Air Temperature ........................ 80°F edb 67°F ewb
Evaporator Air Quantity ...................................... 1225 CFM
External Static Pressure .......................................0.2 in. wg
Electrical Characteristics .......................................230-1-60
II SELECT UNIT BASED ON REQUIRED COOLING
CAPACITY.
Enter Net Cooling Capacities table at condenser entering
temperature of 95°F. The 036 unit at 1225 cfm and 67°F
ewb (entering wet bulb) will provide a total capacity of
36,500 Btuh and a SHC of 27,600 Btuh. Calculate SHC
correction, if required, using Note 4 under Cooling
Capacities tables.
III SELECT ELECTRIC HEAT.
Enter the 036 unit Heating Extended Performance table at
1225 cfm. At 70°F return indoor air and 20°F air entering
outdoor coil, the integrated heating capacity is 20,300 Btuh.
(Select integrated heating capacity value since deductions
for outdoor-coil frost and defrosting have already been
made. No correction is required.)
The required heating capacity is 36,000 Btuh. Therefore,
15,700 Btuh (36,000 – 20,300) additional electric heat is
required
Determine additional electric heat capacity in kW.
15,700 Btuh
3414 Btuh/kW
Enter the Electric Heater table on page 5 for 208/230 v,
single-phase, unit. The 5-kW heater at 240v most closely
satisfies the heating required. To calculate kw at 230v,
multiply the heater kw by multiplication factor 0.92 found in
the Multiplication Factors table on page 17.
5 kW x 0.92 = 4.6 kW
4.6 kW x 3414 Btuh/kW = 15,704 Btuh
Total unit heating capacity is 36,004 Btuh (20,300 + 15,704).
IV DETERMINE FAN SPEED AND POWER
REQUIREMENTS AT DESIGN CONDITIONS.
Before entering the air delivery tables, calculate the total
static pressure required. From the given, Filter Pressure
Drop Table, Electrical Heat Pressure Drop table, and the
Wet Coil Pressure Drop table, find:
External static pressure
0.200 in. wg
Wet Coil Pressure Drop 0.032 in. wg
Filter 0.130 in. wg
Electric Heaters 0.000 in. wg
Total static pressure 0.362 in. wg
Enter the table for Wet Coil Air Delivery — At 0.362 in. wg
external static pressure and high speed, the motor delivers
1235 cfm.
V SELECT UNIT THAT CORRESPONDS TO POWER
SOURCE AVAILABLE.
The Electrical Data table shows that the unit is designed to
operate at 208/230-1-60.
= 4.6 kW of heat required
SELECTION PROCEDURE
1 2
4 3
x
y
CORNER WEIGHTS (SMALL CABINET) CORNER WEIGHTS (LARGE CABINET)
Unit 024 030 036 Unit 042 048 060
Total Weight 350 350 373 Total Weight 440 463 499
Corner Weight 1 70 70 75 Corner Weight 1 88 98 107
Corner Weight 2 54 54 58 Corner Weight 2 68 61 70
Corner Weight 3 84 84 90 Corner Weight 3 106 127 136
Corner Weight 4 141 141 150 Corner Weight 4 177 177 186
Model 604B Model 604B
C00071