Rheem RKKB SERIES Owner's Manual page 5

Also inside the blower compart-
ment is the low-ambient control
( ), low-pressure switch (
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high-pressure switch ( ) and
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freeze stat refrigerant safety
device ( ). The low-ambient
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control allows for operation of the
compressor down to 0 degrees
ambient temperature by cycling
the outdoor fans on high pressure.
The high-pressure switch will
shut off the compressors if
pressures exceeds, 450 PSIG
are detected, this may occur if
the outdoor fan motor fails. The
low-pressure switch shuts off
the compressors if low pressure
is detected due to loss of
charge. The freeze stat protects
the compressor if the evapora-
tor coil gets too cold (below
freezing) due to low airflow. Each factory-installed option is
brazed into the appropriate high or low side and wired appropri-
ately. Use of polarized plugs and sharder fittings allow for easy
field installation.
Inside the blower compartment the interlaced evaporator can
also be viewed. The evaporator uses enhanced fin technology for
maximum heat transfer. The cap-tube metering device assures
even distribution of refrigerant throughout the evaporator.
Wiring throughout the unit
is neatly bundled and
routed. Where wire har-
nesses go through the
condenser bulkhead or
blower deck, a molded wire
harness assembly ( )
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provides an air-tight and
water-tight seal, and pro-
vides strain relief. Care is
also taken to tuck raw
edges of insulation behind sheet metal to improve indoor air
quality.
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UNIT FEATURES & BENEFITS—RKKB/RKMB/RKNB- SERIES
),
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The furnace compartment contains the latest furnace technology
on the market. The draft inducers (
Rheem exclusive in-shot burners (
heat exchanger (
heat exchangers can be factory installed for those applications
that have high fresh-air requirements, or applications in corrosive
environments. Each furnace is equipment with a two-stage gas
valve ( ), which provides two stages of gas heat input. The first
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stage operates at 50% of the second stage (full fire). 81% steady
state efficiency is maintained on both first and second stage by
staging the multiple inducers to optimize the combustion airflow
and maintain a near stioceometric burn at each stage.
The direct spark igniter (
adverse conditions. This is coupled with remote flame sense (
to assure that the flame has carried across the entire length of
the burner assembly. Gas supply can be routed from the side or
up through the base.
Each furnace has the following safety devices to assure consis-
tent and reliable operation after ignition:
• Pressures switches (
before ignition.
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• Rollout switches (
heat exchanger.
• A limit device that protects the furnace from over-temperature
problems.
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) draw the flame from the
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) into the aluminized tubular
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) for clean, efficient gas heat. Stainless steel
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) assures reliable ignition in the most
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) to assure adequate combustion airflow
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) to assure no obstruction or cracks in the
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)
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