Bryant 542F User Manual
DESCRIPTION
Model 542F is a high-efficiency, single-package heat pump that
has an energy efficiency ratio (EER) of 8.5 and a coefficient of
performance (COP) of 3.0 at 47 F outdoor temperature rating
point.
The 542F has supply- and return-air openings on the bottom of
the unit and is designed primarily for rooftop installation on a
factory-supplied 14- or 24-in. high roof curb. The air ducts connect to the curb only; therefore, the curb and ductwork may be
installed before the unit arrives at the jobsite.
A 24-in. high factory-supplied adapter for horizontal supply/
return duct connections to an over-and-under duct configuration
is also available for grade level or rooftop installation.
‘‘Variable circuited’’ indoor and outdoor coils allow both coils to
operate with parallel circuits when they are performing as
evaporators, and with a series of circuits when they are performing as condensers.
STANDARD FEATURES
FACTORY-ASSEMBLED PACKAGE is a compact, fully self-
contained heating/cooling unit that is prewired, prepiped, and
precharged for minimum installation time and expense.
TWO RUGGED, SERVICEABLE, SEMI-HERMETIC COMPRESSORS provide two stages of heating and cooling. These
compressors are electrically and mechanically independent.
COMPRESSOR ISOLATION MOUNTING minimizes vibration
(noise) transmission to building.
TWO SUCTION-TUBE ACCUMULATORS protect compres-
sors against liquid slugging — permitting operation over wide
range of temperatures.
CRANKCASE HEATERS AND FILTER DRIERS are standard.
HIGH-AND LOW-PRESSURE SAFETY DEVICES are included
to prevent major component breakdown when abnormal refrigerant operating conditions occur.
INTERNAL AND EXTERNAL PROTECTION is provided
against compressor overload and overheat conditions.
HIGH-STATIC, BELT-DRIVEN BLOWER with an adjustable
motor pulley permits variable airflow rates. An optional motor
pulley adjusts the airflow range to meet most applications.
WEATHERIZEDCABINET of heavy-duty phosphated and zinccoated steel is standard. Baked-on finish is corrosion and fade
resistant.
VERTICAL CONDENSER AIR DISCHARGE prevents recirculation of hot condenser air and reduces the operating sound
level.
MANUAL OUTDOOR-AIR DAMPER (standard equipment on
units without optional economizer) provides up to 25% outdoor
air for ventilation.
SUPPLEMENTAL ELECTRIC HEATERS are available as accessory equipment for operation on 208, 230, and 460 v, and
are modular in design for easy installation.
SINGLE-POINT POWER CONNECTION is provided on units
with field-installed electric heaters. Only one power supply with
one disconnect switch is required.
PROTECTION AS REQUIRED BY NEC (National Electrical
Code) for fan motors is factory supplied.
TWO-IN. FILTERS are standard.
RIGGING HOLES are provided in unit base rails for a 4-point lift
to facilitate lifting and moving operations.
THERMALLY AND ACOUSTICALLY INSULATED air-handling
section provides quieter and more efficient operation.
FACTORY-INSTALLED OPTIONS
DESCRIPTION AND USAGE
Economizer — The economizer will allow a fixed percentage
(between 0 and 100%) outdoor ventilation air into the unit any
time the indoor fan is running.Adry-bulbchangeoverthermostat
allows up to 100% outdoor air whenever the temperature of the
outdoor air alone will adequately provide cooling. If the economizer alone cannot provide enough cooling, then simultaneous
economizer and compressor operation will provide the most
economical operation.
SUGGESTED USE:
• To allow a fixed percentage of outdoor air any time the indoor
fan is on, or operates in economizer mode if outdoor air can
provide cooling, but closes when the indoor fan is off to prevent cold backdrafts and wasted energy.
• To reduce energy usage. Use whenever the number of hours
of operation at below 55 F is significant.
• The damper may be used on either vertical or horizontal
applications.
Alternate Indoor-Fan Drive — Alternate drive allows operation
of the indoor fan at conditions outside the range of the standard
factory motor and drive combination.
SUGGESTED USE:
• When higher static/airflow is required to meet job conditions.
MODEL 542F
Bryant
Air Conditioning
COMMERCIAL ROOFTOP
PACKAGED HEAT PUMP
Model 542F
Size 180
15 Tons
Form No. PDS 542F.180.2B
FIELD-INSTALLED ACCESSORY
DESCRIPTION AND USAGE
Roof Curbs (Vertical) — Full-perimeter galvanized steel sup-
port frame in 14- and 24-in. high designs provides wood nailer
to attach roof counter flashing. Insulated basepans in curb are
provided to prevent condensation. Ductwork attaches to rails
provided in the roof curb. A gasket is provided to form an airand watertight seal between unit and curb. The gasket meets
the standards of the NRCA (National Roofing Contractors’
Association).
SUGGESTED USE:
• Rooftop application for vertical discharge.
• Slab-mounted applications when elevation of the unit is
necessary.
Horizontal Adapters — The adapters are prefabricated, easily
field-assembled, and permit full perimeter mounting. Adapters
can be installed at the jobsite before unit is installed, eliminating
a major leak source.
SUGGESTED USE:
• Rooftop application for horizontal discharge.
• Rooftop applications for horizontal discharge on units where
high air delivery cfms are required.
Two-Position Damper — Package consists of a low-leak
damper assembly. The damper will allow either 0 or 25% outdoor air into the unit any time the evaporator fan is running.
When the evaporator fan is off, the damper will be closed.
SUGGESTED USE:
• Allows a fixed percentage of outdoor air any time the evaporator fan is on, but closes when the evaporator fan is off to
prevent cold backdrafts and wasted energy.
• The damper may be used on either vertical or horizontal airflow applications.
Thermostats and Subbases — Provide staged cooling and
heating, automatic (or manual) changeover, fan control, and indicator light.
SUGGESTED USE:
• To control unit operations.
Barometric Relief Package — This package is useful when it
is necessary to remove excess pressure from the conditioned
space.
NOTE: Optional economizer is required with this accessory.
Power Exhaust — This package is useful when it is necessary
to remove excess pressure from the conditioned space.
NOTE: Optional economizer is required with this accessory.
SUGGESTED USE:
• When the job requires the ability to relieve internal building
pressure and pressure losses through the return-air ductwork
are greater than 0.20 in. wg.
• When the job requires the ability to move large quantities
of air to relieve pressure in the conditioned space.
Head Pressure Control — Kit consists of an outdoor-air thermostat that permits adequate head pressure control during
cooling operation at low outdoor-ambient temperatures. Refer
to Trade Prices for more details.
SUGGESTED USE:
• When cooling at low-ambient outdoor temperatures is
desired.
Time GuardT Device — Package consists of a control to be
field wired into the unit controls, and provides a 5-minute delay
in compressor operation between cooling cycles.
SUGGESTED USE:
• Prevents compressor short cycling when rapid compressor
cycles may be a problem.
Electric Heat Packages — Each package consists of one or
more heater modules. Each module slides into keyed mounting
slots in the fan discharge section.
SUGGESTED USE:
• To provide heat in the unit when required.
Economizer — See description listed under Factory-Installed
Options Description and Usage section on page 1.
Remote Control Panel — The remote control panel accessory
consists of a decorative, indoor, wall-mounted panel. The panel
contains: 2-stage heat/2-stage cool thermostat with auxiliary
changeover, a system switch with HEAT-COOL-AUTO.-OFF
settings, a fan switch with ON-AUTO. settings, indicator lights
for HEAT-COOL-FAN operation, and 3 unused indicator lights
for field use.
SUGGESTED USE:
• Whenever remote unit operation is desired.
Emergency Heat Package — The emergency heat package includes an emergency heat control box containing: emergency
heat relays, outdoor thermostat(s), and an emergency heat
thermostat subbase with a warning light.
SUGGESTED USE:
• As auxiliary heating system in the event mechanical heating
should be locked out.
CONTENTS
Page
Model Description .................................3
ARI Capacity Ratings ..............................3
Dimensional Drawings .............................4-6
Specifications ....................................7
Selection Procedure ...............................8
Gross Cooling Capacities ...........................9
Integrated Heating Capacities .......................9
Air Delivery .....................................10
Electric Resistance Heater Data .....................11
Electrical Data ...................................11
Operating Sequence ..............................12
Application Data .................................13
Typical Field Wiring .............................14,15
Typical Installation ................................15
Engineers’ Specification Guide ......................16
2
MODEL DESCRIPTION
ODS CATALOG ORDERING NUMBER NOMENCLATURE
ARI* CAPACITY RATINGS
COOLING HEATING-HIGH TEMP HEATING-LOW TEMP
Total
kW
Net
Capacity
(Btuh)
Cfm EER
Total
Capacity
(Btuh)
Total
kW
COP
Total
Capacity
(Btuh)
Total
kW
COP
21.0 162,000 6750 8.5 166,000 17.5 2.8 92,000 14.3 1.8
LEGEND
COP — Coefficient of Performance
db — Dry Bulb
EER — Energy Efficiency Ratio
ESP — External Static Pressure
kW — Kilowatts
wb — Wet Bulb
*Air Conditioning and Refrigeration Institute.
NOTE: 542F180 units are rated in accordance with ARI Standard 340.
Cooling ratings are net values, reflecting the effects of circulating fan
heat. Ratings are based on:
ESP: −.35 in. wg
Cooling Standard: 80 F db, 67 F wb indoor coil entering-air temperature and 95 F outdoor coil entering-air temperature.
High-Temp Heating Standard: 70 F db indoor coil entering-air temperature and 47 F db, 43 F wb outdoor coil entering-air temperature.
Low-Temp Heating Standard: 70 F db indoor coil entering-air temperature and 17 F db, 15 F wb outdoor coil entering-air temperature.
3
DIMENSIONAL DRAWING — BASE UNIT
NOTE: Space required for service clearance and airflow: Allow 68-09 above the unit; 78-09 on filter access panel end; and 48-09 on
remaining sides of unit.
4
DIMENSIONAL DRAWING — HORIZONTAL AND VERTICAL ROOF CURBS AND HORIZONTAL ADAPTER
ACCESSORY
PACKAGE NO.
CURB
HEIGHT
DESCRIPTION ‘‘A’’ ‘‘B’’ ‘‘C’’
308450-201
18-29
(305)
Standard Curb —
149 High
———
308450-202
28-09
(610)
Standard Curb
for Units Requiring
High Installation
———
308450-203
28-09
(610)
Horizontal
Roof Curb
58-69
(1676)
08-2
1
⁄
2
9
(64)
18-69
(457)
389210-201
18-119
(584)
Pre-Assembled,
High-Static
Horizontal
Adapter
68-29
(1880)
08-6
1
⁄
4
9
(159)
18-25⁄
8
9
(371)
LEGEND
COMP SECT. — Compressor Section
NOTES:
1. Roof curb accessory is shipped unassembled.
2. Insulated panels,
1
⁄2-in. thick neoprene-coated,
2 lb density.
3. Dimensions in ( ) are in millimeters.
4. Direction of airflow.
5. Roof curb: 18 gage steel.
6. Attach all ductwork to roof curb.
NOTE: To prevent the hazard of stagnant water build-up in the
drain pan of the indoor-air section, unit can only be pitched as
shown.
5
Loading...