SELECTION PROCEDURE (With 580F240 Example)

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

Given:

Required Cooling Capacity . . . . . . . . . . . . . 230,000 Btuh Sensible Heat Capacity (SHC). . . . . . . . . . . 170,000 Btuh Required Heating Capacity . . . . . . . . . . . . . 215,000 Btuh Condenser Entering Air Temp . . . . . . . . . . 95 F (Summer) Evaporator Entering Air Temp . . . . . . . . . . . . . . .80 F edb,

67 F ewb Evaporator Air Quantity . . . . . . . . . . . . . . . . . . . 8,000 cfm External Static Pressure . . . . . . . . . . . . . . . . . . 0.6 in. wg Electrical Characteristics (V-Ph-Hz). . . . . . . . . . . 460-3-60

Vertical discharge unit with optional EconoMi$er IV required.

edb — Entering dry-bulb ewb — Entering wet-bulb

IISELECT UNIT BASED ON REQUIRED COOLING CAPACITY.

Enter Cooling Capacities table for 580F240 (page 183) at condenser entering temperature 95 F, evaporator air entering at 8,000 cfm and 67 F wb. The unit will provide a total cooling capacity of 249,000 Btuh and a sensible heat- ing capacity (SHC) of 188,000 Btuh. For air entering evap- orator at temperatures other than 80 F edb, calculate SHC correction as required.

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

IIISELECT HEATING CAPACITY OF UNIT TO PROVIDE DESIGN CONDITION REQUIREMENTS.

In the ARI Heating Capacities and Efficiencies table note that the 580F240360 will provide an output capacity of 292,000 Btuh, which is adequate for the given application.

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. From the given and the Accessory/FIOP Static Pressure table on page 191 find:

External static pressure

0.60 in. wg

EconoMi$er IV static pressure

0.10 in. wg

Total static pressure

0.70 in. wg

Enter the Fan Performance table 580F240360 at 8,000 cfm and 0.70 in. wg external static pressure. By interpolation, find that the rpm is 1243 and the watts are 5368.

VDETERMINE NET COOLING CAPACITY.

Cooling capacities are gross capacities and do not include indoor (evaporator) fan motor (IFM) heat. Use the watts input power to the motor calculated in Section IV above.

IFM Watts = 5368

Determine net cooling capacity using the following formula:

Net capacity = Gross capacity – IFM heat = 249,000 Btuh – 5368 Watts

(3.412 WattsBtuh )

=249,000 Btuh – 18,316 Btuh

=230,684 Btuh

Net sensible capacity = 188,000

Btuh – 18,316 Btuh

= 169,684

Btuh

The calculations show that a 580F240360 unit with the standard motor and standard low-medium static drive is the correct selection for the given conditions.

580F180-300

181

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Bryant 581A/B manual Selection Procedure With 580F240 Example, II Select Unit Based on Required Cooling Capacity
Page 180 Page 182

581A/B specifications

The Bryant 581A/B is a sophisticated rooftop unit designed for commercial heating and cooling applications, striking a balance between performance, efficiency, and versatility. This unit is engineered to cater to various building sizes and configurations, making it an excellent choice for businesses seeking reliable climate control solutions.

One of the standout features of the Bryant 581A/B is its high efficiency. With SEER ratings reaching up to 14.5, this unit can significantly reduce energy costs while providing optimal performance throughout its operational lifespan. The design incorporates advanced compressor technology, allowing for variable speed operation that not only enhances comfort but also promotes energy savings by adjusting to the real-time demands of the environment.

The Bryant 581A/B also integrates cutting-edge refrigerant technology. Utilizing Puron refrigerant, it adheres to current environmental standards, minimizing its impact on ozone depletion while maximizing cooling performance. This commitment to sustainability is complemented by energy-efficient components, including high-efficiency coils and fan motors, which further optimize energy consumption.

In terms of construction, the Bryant 581A/B is built to withstand the rigors of outdoor installation. The unit features a rugged cabinet design with durable, corrosion-resistant materials, ensuring long-term reliability even in challenging weather conditions. Additionally, the easily accessible components simplify maintenance, reducing downtime for businesses.

The functionality of the Bryant 581A/B extends beyond mere cooling and heating. It is equipped with advanced control systems that can be interfaced with building management systems, allowing for seamless integration and enhanced control over indoor climate. This technology provides operators with the ability to monitor and adjust settings remotely, ensuring a comfortable indoor environment while optimizing energy use.

Noise reduction is another important characteristic of the Bryant 581A/B. The unit is designed with sound-dampening features, making it suitable for applications where low noise levels are a priority, such as retail spaces or office buildings.

Overall, the Bryant 581A/B is a robust solution for businesses seeking efficient, reliable, and flexible climate control. Its combination of advanced technology, durable construction, and user-friendly features make it a leading choice in the commercial HVAC market.
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