User Guide
Table Of Contents
- Product Data
- Features/Benefits
- Model Number Nomenclature
- AHRI Capacities
- Unit Dimensions
- Unit Dimensions
- 36-60
- Accessory Dimensions
- 1. Roof curb must be set up for unit being installed.
- 2. Seal strip must be applied, as required, to unit being installed.
- 3. Roof curb is made of 16-gauge steel.
- 4. Attach ductwork to curb (flanges of duct rest on curb).
- 5. Insulated panels: 1-in. (25.4 mm) thick fiberglass 1 lb. density.
- Performance Data
- Application Data
- Electrical Data
- Connection Wiring Schematic 208/230-1-60
- Controls
- Operating Sequence
- 2. The normally open contacts of energized contactor (C) close and complete the circuit through compressor motor (COMP) to condenser (outdoor) fan motor (OFM). Both motors start instantly.
- 3. The set of normally open contacts on the interface fan board (IFB) are closed which energizes a circuit to the indoor fan motor (IFM).
- Guide Specifications
- Packaged Gas Heating/Electric Cooling Units Constant Volume Application
- HVAC Guide Specifications
- General
- Products
- Guide Specifications (Continued)
- 2. Compressor Start Kit (single phase units only):
- 3. Thermostat:
- 4. Crankcase Heater:
- 5. Economizer:
- 6. Filter Rack Kit:
- 7. Flat Roof Curb:
- 8. Flue Discharge Deflector
- 9. Low Ambient Package:
- 10. Manual Outdoor Air Damper:
- 11. Square-To-Round Duct Transitions (24-48 models):
- 12. Time Guard II
- 13. Low Pressure Switch Kit
577C--K Ultra Low NOx: Product Data
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
25
Typical Piping and Wiring
A09230
A09231
Application Data
Condensate trap — A 2-in. (50.8 mm) condensate trap must be field
supplied.
Ductwork — Secure downflow discharge ductwork to roof curb. For
horizontal discharge applications, attach ductwork to unit with flanges.
To convert a unit to downflow discharge — Units are equipped with
factory-installed inserts in the down-flow openings. Removal of the
inserts is similar to removing an electrical knock-out. Use the duct cover
to seal the horizontal discharge openings in the unit. Units installed in
horizontal discharge orientation do not require duct covers.
Airflow — Units are draw-thru in the cooling mode and blow-thru in the
heating mode.
Maximum cooling airflow — To minimize the possibility of
condensate blow-off from the evaporator, airflow through the units
should not exceed 450 CFM per ton.
Minimum cooling airflow — Minimum cooling airflow is 350 cfm per
ton.
Minimum ambient cooling operation temperature — All standard
units have a minimum ambient operating temperature of 40_F (4_C).
With accessory low ambient temperature kit, units can operate at
temperatures down to 0_F (-17_C).
Minimum temperature — Air entering the heat exchanger in heating
mode must be a minimum of 50_F (10_C) continuous and/or 45_F (7_C)
intermittent.
ROOF
RETURN-AIR
FLEXIBLE DUCT
CEILING
CONCENTRIC DIFFUSER BOX
(FIELD-SUPPLIED)
SUPPLY-AIR
FLEXIBLE DUCT
ROOF-MOUNTING
CURB
INDOOR
THERMOSTAT
DISCONNECT
PER NEC*
FROM
POWER
SOURCE
RETURN
AIR
TOP COVER
FROM
GAS LINE
*NEC - NATIONAL ELECTRICAL CODE