LEGEND AND NOTES FOR TABLE 2

LEGEND

FLA — Full Load Amps

HACR — Heating, Air Conditioning and Refrigeration

IFM — Indoor (Evaporator) Fan Motor

LRA — Locked Rotor Amps

MCA — Minimum Circuit Amps

MOCP— Maximum Overcurrent Protection

NEC — National Electrical Code

OFM — Outdoor (Condenser) Fan Motor

RLA — Rated Load Amps

*Heater capacity (kW) is based on heater voltage of 208, 240, 480, and 575-V. If power distribution voltage varies from rated heater voltage, heater kW will vary accordingly.

†Used to determine minimum disconnect per NEC.

NOTES:

1.

In compliance with NEC requirements for multimotor and combination load equip-

 

ment (refer to NEC Articles 430 and 440), the overcurrent protective device for the

 

unit shall be fuse or HACR breaker.

2.

Unbalanced 3-Phase Supply Voltage

Example: Supply voltage is 460-3-60.

AB = 452 v

BC = 464 v

AC = 455 v

452 + 464 + 455

Average Voltage =

3

=1371

3

=457

Determine maximum deviation from average voltage. (AB) 457 – 452 = 5 v

(BC) 464 – 457 = 7 v (AC) 457 – 455 = 2 v

Maximum deviation is 7 v.

Determine percent of voltage imbalance.

Never operate a motor where a phase imbalance in supply voltage is greater than

% Voltage Imbalance = 100 x

7

2%. Use the following formula to determine the percent of voltage imbalance.

% Voltage Imbalance

max voltage deviation from average voltage

= 100 x

average voltage

457

= 1.53%

This amount of phase imbalance is satisfactory as it is below the maximum allow- able 2%.

IMPORTANT: If the supply voltage phase imbalance is more than 2%, contact your local electric utility company immediately.

3.Non-fused disconnect switch cannot be used when rooftop unit electrical ratings exceed 80 amps.

Table 3 — Electric Heater Usage

UNIT

VOLTAGE

ACCESORY

ACCESSORY HEATER

ACCESSORY SINGLE POINT BOX

PART NUMBER

PART NUMBER

551B

(60 Hz)

 

kW

 

CRHEATER---A00

CRSINGLE---A00

 

 

 

 

 

 

7.8/

9.6/10.4

017

006

 

208/230/240

12.0/14.7/16.0

010

006

 

(3 phase)

18.6/22.8/24.8

011

007

 

 

24.0/29.4/32.0

012

007

 

 

31.8/39.0/42.4

012+017

009

090

 

12.8/13.9

016

006

 

460/480

15.2/16.5

013

006

 

(3 phase)

25.6/27.8

014

006

 

 

30.4/33.0

015

006

 

 

38.4/41.7

014+016

008

 

575

 

17.0

018

006

 

(3 phase)

 

34.0

019

006

 

 

7.8/

9.6/10.4

017

011

 

208/230/240

12.0/14.7/16.0

010

011

 

(3 phase)

18.6/22.8/24.8

011

012

 

 

24.0/29.4/32.0

012

012

 

 

31.8/39.0/42.4

012+017

015

102

 

12.8/13.9

016

011

 

460/480

15.2/16.5

013

011

 

(3 phase)

25.6/27.8

014

011

 

 

30.4/33.0

015

011

 

 

38.4/41.7

014+016

014

 

575

 

17.0

018

011

 

(3 phase)

 

34.0

019

011

 

 

7.8/

9.6/10.4

017

011

 

208/230/240

12.0/14.7/16.0

010

012

 

(3 phase)

24.0/29.4/32.0

012

012

 

 

31.8/38.9/42.4

012+017

015

 

 

37.5/46.0/50.0

010+012

015

120

 

12.8/13.9

016

011

460/480

15.2/16.5

013

011

 

(3 phase)

30.4/33.0

015

011

 

 

38.4/41.7

014+016

014

 

 

46.0/50.0

013+015

014

 

575

 

17.0

018

011

 

(3 phase)

 

34.0

019

011

 

 

 

51.0

018+019

014

 

 

7.8/

9.6/10.4

017

012

 

208/230/240

12.0/14.7/16.0

010

012

 

(3 phase)

24.0/29.4/32.0

012

012

 

 

31.8/38.9/42.4

012+017

015

 

 

37.5/46.0/50.0

010+012

015

150

 

12.8/13.9

016

011

460/480

15.2/16.5

013

011

 

(3 phase)

30.4/33.0

015

011

 

 

38.4/41.7

014+016

014

 

 

46.0/50.0

013+015

014

 

575

 

17.0

018

011

 

(3 phase)

 

34.0

019

014

 

 

 

51.0

018+019

014

NOTES:

1.The rated heater voltage is 240, 480, and 575 v. If power distribution voltage varies from rated heater voltage, heater kW vary accordingly.

2.To determine heater kW at voltages other than those shown in table, use the following formula: Heater kW new = Heater kW rated x (unit power distribution voltage / rated heater voltage) 2

As an example:

For a 16 kW heater rated at 240 v with a power distribution voltage of 215 v kW new = 16 kW (215/240) 2

kW new = 12.8 kW (rating at 215 v)

10

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Bryant 551B installation instructions Electric Heater Usage, †Used to determine minimum disconnect per NEC

551B 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.

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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.