Bryant 558F, 551B, 551A manual Application Data, Maximum Operating Outdoor-Air Temperature

APPLICATION DATA

1.CONDENSATE DRAIN PAN — A sloped condensate drain pan is supplied on all units. The condensate drain pan must be externally trapped. Condensate drains are located on both the bottom and end of the unit. The bottom drain can be used for thru-the-curb connections.

2.DUCTWORK — All ductwork must be attached to flanges. If no flanges are present, they must be field supplied. Secure vertical discharge ductwork to roof curb. For horizontal dis- charge applications, attach ductwork to flanges. Field- supplied flanges can be attached to horizontal discharge openings and all ductwork attached to flanges.

3.THRU-THE-BOTTOM SERVICE CONNECTIONS — Thru- the-bottom connections allow field power wires and control wires to enter through the basepan.

4.THERMOSTAT — Use of 2-stage cooling thermostat is recommended for all units equipped with economizer.

5.HEATING-TO-COOLING CHANGEOVER — All units are automatic changeover from heating to cooling when auto- matic changeover thermostat and subbase are used.

6.AIRFLOW — Units are draw-thru on cooling and blow-thru on heating.

7.MAXIMUM AIRFLOW — To minimize possibility of conden- sate blow-off from evaporator, airflow through units should not exceed 500 cfm/ton.

8.MINIMUM AIRFLOW — Minimum airflow for cooling is 300 cfm/ton for unit sizes 036-240, 280 cfm/ton for size 300.

9.MINIMUM AMBIENT OPERATING TEMPERATURE — Minimum operating temperature for standard 036-150 units is 25 F, for standard 155-300 units is 40 F. With accessory Motormaster® or Motormaster IV control, units can operate at outdoor temperatures down to –20 F.

10.MAXIMUM OPERATING OUTDOOR-AIR TEMPERATURE

— Maximum outdoor-air operating temperature for cooling is 125 F (115 F for 558F036-150 units).

11.MOTOR DATA — Due to Bryant’s internal unit design (draw- thru over the motor), air path, and specially designed motors, the full horsepower (maximum continuous bhp) listed in the Physical Data table and in each Fan Perfor- mance table can be utilized with extreme confidence.

Using Bryant motors to the values listed in the Physical Data, Fan Performance, and Evaporator-Fan Motor Data tables will not result in nuisance tripping or premature motor failure. In addition, the unit warranty will not be affected.

12.PERFECT HUMIDITY™ DEHUMIDIFICATION PACKAGE

— This option provides greater dehumidification by further subcooling the hot liquid refrigerant leaving the condenser coil. The Perfect Humidity package consists of a subcooling coil located on the leaving-air side of the evaporator coil. The location of the coil in the indoor airstream enhances the latent capacity of the rooftop units by up to 40%.

Many buildings suffer damage or have poor indoor-air qual- ity due to overly humid conditions. Building humidity must be controlled for the following reasons:

a.INDOOR-AIR QUALITY — Humidity is a major factor in the growth and propagation of mold and mildew in a building. The mold and mildew can spread quickly and grow in carpets and ductwork and on walls, and often causes cases of sick building syndrome. This syndrome can lead to employee absenteeism due to illness, lower worker productivity, and increased health care costs. The American Society of Heating, Refrigeration, and Air Con- ditioning Engineers (ASHRAE) recommends that relative humidity levels in buildings be maintained below 70%.

b.COMFORT LEVELS — High humidity levels cause the occupied space to become uncomfortable, because humidity interferes with the body’s natural cooling pro- cess (evaporation at the skin surface).

1'-10 11/16''	6'-2 3/8'' MAX.
MAX.	5'-9 3/16'' MAX.

5 3/16''

1'-0 3/16''

4'-6 13/16'' 1'-7 15/16''

1'-0 3/16''

24'' MIN.

B

B

A

NOTE:

1.Do not drill in this area, damage to basepan may result in water leak.

2.A 90-degree elbow must be provided in the supply ductwork to comply with UL (Underwriters’ Laboratories) codes for use with electric heat.

Concentric Duct Distribution —

Unit Sizes 155-300

A

BAFFLE

Shaded area indicates block-off panels.

NOTE: Dimensions A, A′ and B, B′ are obtained from field-supplied ceiling diffuser.

CAUTION: Concentric ducts may only be installed on units without electric heat. Personal injury or unit damage may result.

Concentric Duct Details — Unit Sizes 155-300

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