SELECTION PROCEDURE

I DETERMINE COOLING AND HEATING REQUIRE- MENTS AT DESIGN CONDITIONS.

Given:

Required Gross Cooling

Capacity (TC) . . . . . . . . . . . . . . . . . . . . . . 168,000 Btuh Gross Sensible Heat

Capacity (SHC) . . . . . . . . . . . . . . . . . . . . 121,000 Btuh Required Heating Capacity . . . . . . . . . . . . . 110,000 Btuh Condenser Entering Air Temperature . . . . . . . . . . . . 95 F Indoor Air Temperature . . . . . . . . . . . . 80 F edb, 67 F ewb Evaporator Air Quantity . . . . . . . . . . . . . . . . . . . 6,000 cfm External Static Pressure . . . . . . . . . . . . . . . . . 1.45 in. wg Electrical Characteristics (V-Ph-Hz). . . . . . . . . . . 230-3-60

IISELECT UNIT BASED ON REQUIRED COOLING CAPACITY.

Enter Cooling Capacities table for 551A180 at condenser entering temperature of 95 F, evaporator air quantity of 6,000 cfm, and indoor air temperature of 67 F. The 551A180 unit will provide a total cooling capacity of 190,000 Btuh and a SHC of 136,000 Btuh. For evaporator air temperatures other than 80 F, calculate SHC correction using formula in notes under cooling capacity tables.

Unit meets design conditions for TC and SHC.

NOTE: Unit ratings are gross capacities and do not include the effect of indoor fan motor heat. To calculate net capacities, see Step V.

III SELECT ELECTRIC HEAT.

Enter the Accessory/FIOP Static Pressure — 551A155- 180 Units table at the selected unit size, cfm, and kW heater size to determine heater pressure drop.

Calculate pressure drop:

 

Design External Static Pressure

1.45

56 kW Heater Static Pressure

+0.12

1.57 in. wg (ESP)

Enter Fan Performance tables for 551A180 at 6,000 cfm and 1.57 in. wg. The rpm is 1184 and the Bhp is

4.43(interpolation required). The factory-installed 5 hp motor and alternate high-static drive are sufficient for this operation.

VDETERMINE NET COOLING CAPACITIES.

Cooling capacities are gross capacities and do not include indoor (evaporator) fan motor (IFM) heat. To determine input power to the motor, enter the Fan Performance tables for 551A180 at 6,000 cfm and 1.57 in. wg. Input watts to the motor are 3772 (interpolation required).

Determine net cooling capacity and net sensible cooling capacity using the following formulas:

IFM Heat = Input Watts x 3.412 Btuh/Watt

=3772 x 3.412

=12,870 Btuh

Net Capacity = Gross Capacity – IFM Heat

=190,000 – 12,870

=177,130 Btuh

Heating load required is 110,000 Btuh.

110,000 Btuh

Net Sensible Cap. = Gross Sensible Cap. – IFM Heat

=136,000 – 12,870

=123,130 Btuh

3.412 Btu/W

= 32,239 Watts Required

= 32.2 kW required

The calculations show that a 551A180 unit with the 56 kW heater is the correct selection for the given conditions.

Enter the Electric Resistance Heater Data table, on page 150, for the 551A180 unit at 230-3-60. The 56 kW (52 kW at 230 v) heater most closely satisfies the heat required.

IV DETERMINE FAN SPEED AND POWER REQUIRE- MENTS AT DESIGN CONDITIONS.

Before entering the Fan Performance tables, calculate the total static pressure required based on unit components. Tabulated fan performance includes filters and wet evapo- rator coil. Refer to Accessory/FIOP Static Pressure table for added pressure drops.

VI SELECT THE UNIT THAT CORRESPONDS TO POWER SOURCE AVAILABLE.

The electrical data table shows that the 230-3-60 unit is available.

551A155-180

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Bryant 551B, 558F manual Selection Procedure, V Determine Net Cooling Capacities, 551A155-180, Iii Select Electric Heat
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551A, 551B, 558F specifications

The Bryant 551B and 551C are two highly efficient air conditioning units designed to provide optimal comfort in residential settings. Known for their reliability and performance, these models are part of Bryant's esteemed line of heating and cooling solutions.

One of the standout features of the Bryant 551B is its two-stage cooling system, which allows for better humidity control and increased comfort. This ensures that homeowners can enjoy consistent temperatures while reducing energy consumption. The unit operates quietly, thanks to its noise-reducing technology, making it an ideal choice for bedrooms and living spaces.

On the other hand, the Bryant 551C builds upon this foundation with its variable-speed compressor. This technology allows the unit to adjust its cooling output according to the specific needs of the home. This results in seamless operation and even greater energy efficiency. Both models also incorporate Bryant's advanced control capabilities, which allow users to monitor and adjust settings remotely via smart devices, adding a layer of convenience and modernity to home climate control.

With an emphasis on durability, both the 551B and 551C feature a galvanized steel cabinet that protects against weather-related damage. The powder coat finish further enhances their resistance to rust and corrosion, ensuring a long lifespan and minimal maintenance.

Another significant characteristic of these units is their excellent Seasonal Energy Efficiency Ratio (SEER) ratings. The 551B boasts a SEER rating of up to 16, while the 551C takes it even further with ratings exceeding 20. This efficiency not only translates to lower energy bills for homeowners but also contributes to a reduced carbon footprint, making these units environmentally friendly options.

Both models are also designed to operate with eco-friendly refrigerants, aligning with modern energy standards and regulations aimed at reducing greenhouse gas emissions.

In summary, the Bryant 551B and 551C are exemplary choices for homeowners looking for reliable, efficient, and high-performing air conditioning solutions. With features such as two-stage and variable-speed compressors, advanced smart technology, and robust construction, these models stand out in the competitive HVAC market. They promise a comfortable indoor environment along with significant energy savings, making them a wise investment for the future.
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