Carrier manual 50XP UNIT SUGGESTED RIGGING, Selection Procedure With Example

50XP UNIT SUGGESTED RIGGING

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(914 mm)

DETAIL A

3					4
						A07216							A08005
			SMALL CABINET							LARGE CABINET
Unit*	024	024	030	030	036	036	Unit*	042	042	048	048	060	060
	lb	kg	lb	kg	lb	kg		lb	kg	lb	kg	lb	kg
Rigging	345	156	349	158	367	166	Rigging	425	193	459	208	504	229
Weight							Weight

NOTE: See dimensional drawing for corner weight distribution. Corner weights shown on drawing are based on unit---only weights and do not include pack- aging.

50XP

SELECTION PROCEDURE (WITH EXAMPLE)

1.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 . . . . . . . . . . . . . . . 15,000 Btuh Condenser Entering Air Temperature . . . . . . . . 95°F(35°C)

Indoor-Air Temperature . . . . . . . . . . . . . 80°F (26°C) edb 67°F (19°C) ewb

Evaporator Air Quantity . . . . . . . . . . . . . . . . . . 1200 CFM External Static Pressure . . . . . . . . . . . . . . . . . 0.20 IN. W.C. Electrical Characteristics . . . . . . . . . . . . . . . . . . . 230-1-60

2. Select unit based on required cooling capacity.

Enter Net Cooling Capacities table at condenser entering temperature of 95°F (35°C). The 036 unit at 1225 CFM and 67°F (19°C) 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.

4.Determine fan speed and power requirements at design conditions.

Before entering the air delivery tables, calculate the total static pressure required. From the given example, the Filter Pressure Drop Table, and the Accessory Electric Heat Pressure Drop table, find:

External Static Pressure	0.200 IN. W.C.
Filter	0.130 IN. W.C.
Wet Coil Pressure Drop	0.032 IN. W.C.
Total Static Pressure	0.362 IN. W.C.

Enter the table for Dry Coil Air Delivery—At 0.362 IN. W.C. ESP (external static pressure) and NOM speed pin selection, the motor will deliver 1235 cfm.

5.Select unit that corresponds to power source available.

The Electrical Data Table shows that the unit is designed to operate at 208-1-60.

3. Select electric heat.

The required heating capacity is 15,000 Btuh.

Determine additional electric heat capacity in kW.

15,000 Btuh	= 4.4kW of heat required
3,414 Btuh/kW

Enter the Electric Heater Packages table for 208/240, single-phase, 036 unit. The 5 kW heater at 240v most closely satisfies the heating required. To calculate kW at the 208v, multiply the heater kW by multiplication factor 0.75 found in the Wattage Multiplication Factors table.

5 kW x 0.75 = 3.75 kW

3.75 kW x 3414 = 12,802.50 Btuh

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