Carrier manual 50XT SUGGESTED RIGGING, Selection Procedure, Select electric heat

50XT SUGGESTED RIGGING

-in. (914 mm)

DETAIL A

A06298

SELECTION PROCEDURE

Determine cooling and heating requirements at design conditions

Given:

REQUIRED COOLING CAPACITY (TC) . . . . . . 34,500 BTUH SENSIBLE HEAT CAPACITY (SHC) . . . . . . . . . 24,000 BTUH REQUIRED HEATING CAPACITY (SHC) . . . . . 36,000 BTUH CONDENSER ENTERING AIR TEMPERATURE 95°F (35°C)

INDOOR-AIR TEMPERATURE . . . 80°F (26.6°C) EDB, 67°F (19.4°C) EWB

EVAPORATOR AIR QUANTITY . . . . . . . . . . . . . . . 1200 CFM ELECTRICAL CHARACTERISTICS . . . . . . . . . . . . . 230-1-60

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 1200 cfm and 67°F (19.4°C) ewb (entering wet bulb) will provide a total capacity of 34,600 Btuh and a SHC of 24,220 Btuh. Calculate SHC correction, if required, using Note 4 under Cooling Capacities tables.

Select electric heat

Enter the 036 unit Heating Extended Performance table at 1200 cfm. At 70°F (21.1°C) return indoor air and 20°F (-6.6°C) air entering outdoor coil, the integrated heating capacity is 16,810 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, at least 19,190 Btuh additional electric heat is required.

Determine additional electric heat capacity in kW.

19,190 Btuh

3414 Btuh/kW

= 5.6kW of heat required

			A06296
CABINET	MODEL	RIGGING WT
		lb	kg
Small	50XT--024	418	190
	50XT--030	448	203
	50XT--036	469	213
Large	50XT--042	491	223
	50XT--048	497	225
	50XT--060	548	249
NOTE: See dimensional drawing for corner weight distribution. Corner
weights shown on drawing are based on unit---only weights and do
not include packaging.

Enter the Electric Heater table on page 5 for 208/230v, single-phase, unit. The 7.2-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 29.

7.2 kW x 0.92 = 6.6 kW

6.6kW x 3414 Btuh/kW = 22,532 Btuh Total unit heating capacity is 39,342 Btuh (16,810 + 22,532).

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.

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