Rheem RKKB SERIES, Owner'S Manual, Page: 58 / 68

58
MECHANICAL SPECIFICATIONS—RKKB/RKMB/RKNB- SERIES
General
Units shall be convertible airflow. Operating
range for units with electromechanical
controls shall be between 125°F (51.7°C)
and 50°F (4.4°C). Cooling performance
shall be rated in accordance with DOE
and/or ARI testing procedures. All units
shall be factory assembled, internally
wired, fully charged with R-22, and 100
percent run-tested before leaving the
factory. Wiring internal to the unit shall
be colored and numbered for simplified
identification. Units shall be UL listed
and labeled, classified in accordance to
ANSI-Z21.47 for gas fired central furnaces
and UL 1995/CAN/CSA No. 236-M90 for
central cooling air conditioners. Canadian
units shall be CUL certified.
Casing
Unit casing shall be constructed of zinc
coated, heavy gauge, galvanized steel.
Exterior surfaces shall be cleaned, phos-
phatized, and finished with a weather-
resistant baked enamel finish. Unit’s sur-
face shall be tested 1000 hours in a salt
spray test in compliance with ASTM B117.
Cabinet construction shall allow for all
maintenance on one side of the unit. All
exposed vertical panels and top covers in
the indoor air section shall be insulated
with a cleanable foil faced, fire retardant
permanent, odorless glass fiber material
and secured with adhesive and mechani-
cal fasteners. The base of the unit shall be
insulated with foil-faced material. All insula-
tion edges shall be either captured or
sealed. The unit’s base pan shall have no
penetrations within the perimeter of the
curb other than the raised 1-1/8
[28.58
mm] high downflow supply return openings
to provide an added water integrity precau-
tion. The base rails of the unit shall have
provisions for forklift and crane lifting, with
forklift capabilities on three sides of
the unit.
Unit Top
The indoor top cover shall be one-piece
construction, it shall not be double-
hemmed and gasket-sealed.
Filters
Two inch [50.8 mm], throwaway filters shall
be standard on all units.
Compressors
Units shall have direct-drive, hermetic,
scroll type compressors with centrifugal
type oil pumps. Motor shall be suction gas-
cooled and shall have a voltage utilization
range of plus or minus 10 percent of unit
nameplate voltage. Internal overloads shall
be provided with the scroll compressors.
The compressor shall have external isola-
tion to minimize noise.
Refrigerant Circuits
Each refrigerant circuit shall have capillary
tubes expansion device. Service pressure
ports, shall be factory-installed as standard.
Evaporator And Condenser Coils
Internally finned, 3/8 [9.53 mm] copper
tubes mechanically bonded to a configured
aluminum plate fin shall be standard. Coils
shall be leak tested at the factory to ensure
pressure integrity. The evaporator coil and
condenser coil shall be leak tested to 200
psig and pressure tested to 450 psig. A
sloped condensate drain pan shall be
standard.
Gas Heating Section
The heating section shall have a tubular
heat exchanger design using Rheem exclu-
sive burners and corrosion resistant steel
throughout. An induced draft combustion
blower shall be used to pull the combustion
products through the firing tubes. The
heater shall use a direct spark ignition
(DSI) system and Remote Flame Sense.
On initial call for heat, the combustion
blower shall purge the heat exchanger for
30 seconds before ignition after two unsuc-
cessful ignition attempts on low fire and two
unsuccessful attempts on high fire, the
entire heating system shall be locked out
for one hour or until manually reset at the
thermostat/zone sensor. Units shall be
suitable for use with natural gas or propane
(field-installed kit).
Outdoor Fans
The outdoor fans shall be direct-drive
statically and dynamically balanced, draw-
through in the vertical discharge position.
The fan motor shall be permanently
lubricated and shall have built-in thermal
overload protection.
Indoor Fans
All 3-phase units offer belt drive, FC cen-
trifugal fans with adjustable motor sheaves.
All motors shall be thermally protected. All
indoor fan motors meet the U.S. Energy
Policy Act of 1992 (EPACT).
Controls
Unit shall be completely factory wired with
necessary controls and contactor pressure
lugs or terminal block for power wiring.
Units shall provide an external location
for mounting a fused disconnect device.
24-volt electromechanical control circuit
shall include control transformer and
contactor pressure lugs for power wiring.
Unit shall have single point power entry
as standard.
Accessories/Option
Roof Curb— The roof curb shall be
designed to mate with the unit’s downflow
supply and return openings and provide
support and a watertight installation when
installed properly. The roof curb design
shall allow field-fabricated rectangular
supply/return ductwork to be connected
directly to the curb. Curb design shall
comply with NRCA requirements. Curbs
shall be shipped knocked down for toolless
field assembly and shall include wood
nailer strips.
Economizer— This accessory shall be
either field or factory-installed and is avail-
able with barometric relief standard. The
assembly includes direct drive gear driver,
fully modulating 0-100 percent motor and
dampers, minimum position setting, mixed
air sensor, wiring harness with plug, and
single enthalpy control. Optional differential
enthalpy control shall be field-installed.
The factory-installed economizer arrives
ready for operation.
Remote Potentiometer— Field installed,
the minimum position setting of economizer
shall be adjusted with this accessory.
Motorized Outside Air Dampers—
Field-installed manually set outdoor air
dampers shall provide up to 50 percent
outside air. Once set, outdoor air dampers
shall open to set position when indoor fan
starts. The damper shall close to the full
closed position when indoor fan shuts
down.
Manual Outside Air Damper— Factory or
field-installed rain hood and screen shall
provide up to 50 percent outside air.
Oversized Motors— Factory installed belt
drive oversized motors shall be available for
high static applications.