Engineering Guide Specifications - Johnson Controls RC Series Engineering Manual

Engineering Guide Specifi cations
General
Furnish and install Water Source Heat Pumps, as indicated on the
plans. Equipment shall be completely assembled, piped and internally
wired. Chassis shall be installed with factory built cabinet or other
approved custom cabinet. Chassis SHALL NOT be installed without
an approved cabinet enclosure. Capacities and characteristics as
listed in the schedule and the specifications that follow. The reverse
cycle heating/cooling units shall be floor mounted console type with
horizontal air inlet and up-fl ow air discharge. Units shall be AHRI/ISO
13256-1 certifi ed and listed by a nationally recognized safety-testing
laboratory or agency, such as ETL Testing Laboratory. Each unit shall
be computer run-tested at the factory with conditioned water and
operation verifi ed to catalog data. Each unit shall be mounted on a
pallet and shipped in a corrugated box or stretch-wrapped. The units
shall be designed to operate with entering liquid temperature between
20°F and 120°F [-6.7°C and 48.9°C].
Chassis and Cabinet
The cabinet shall be fabricated from heavy-gauge galvanized steel
and finished with a beige textured epoxy powder coating on both
sides for added protection. This corrosion protection system shall
meet the stringent 1000 hour salt spray test per ASTM B117.
The cabinet shall be easily removable to allow for ease of service
to the controls compartment, chassis, and piping. The top of the
cabinet and grille is a horizontally flat (optional sloped) surface with
a hinged control door cover. The return air filter shall be 1" (25.4
mm) fiberglass disposable type media.
The return and supply air sections are insulated with a 1/4" (6.4 mm)
thick, dual density, 2 lb/ft3 (32 kg/m3) coated mat glass fiber with
edges sealed or tucked under flanges to prevent the introduction
of glass fibers into the discharge supply air through the aluminum
grille. Standard cabinet panel insulation must meet NFPA 90A
requirements, air erosion and mold growth limits of UL-181, stringent
fungal resistance test per ASTM-C1071 and ASTM G21, and shall
meet zero level bacteria growth per ASTM G22. Unit insulation must
meet these stringent requirements or unit(s) will not be accepted.
Option: A Super Quiet Sound package shall include multi-density
full coverage compressor blanket.
Option: Shipped with motorized outside air damper and
damper assembly for 25% make-up air.
The drain pan shall be of stainless steel construction to inhibit
corrosion and bacterial growth. Drain outlet shall be located on pan
as to allow complete and unobstructed drainage of condensate.
The unit as standard will be supplied with solid-state electronic
condensate overflow protection with Aurora Base Control.
Mechanical float switches WILL NOT be accepted. Condensate
tube shall be constructed of stainless steel and have an internal
factory installed condensate trap.
Refrigerant Circuit
All units shall utilize the non-ozone depleting and low global
warming potential refrigerant R410A. All units shall contain a
sealed refrigerant circuit including a hermetic motor-compressor,
bi-directional thermostatic expansion valve, finned tube air-to-
refrigerant heat exchanger, reversing valve, coaxial tube water-to-
refrigerant heat exchanger, and service ports.
Compressors shall be high-efficiency single speed rotary type
designed for heat pump duty and mounted on durometer grommets
to provide vibration free compressor mounting. Compressor motors
shall be single-phase PSC with internal overload protection.
The air coil shall be sized for low-face velocity and constructed of
lanced aluminum fins bonded to rifled aluminum tubes in a staggered
pattern not less than three rows deep for enhanced performance.
Option: AlumiSeal electro-coated air coil.
The coaxial water-to-refrigerant heat exchanger shall be designed
for low water pressure drop and constructed of a convoluted copper
(cupronickel option) inner tube and a steel outer tube. Refrigerant
to air heat exchangers shall utilize enhanced corrugated lanced
aluminum fins and rifled aluminum tube construction rated to
withstand 600 psig (4135 kPa) refrigerant working pressure.
Refrigerant-to-water heat exchangers shall be of copper inner
water tube and steel refrigerant outer tube design, rated to
withstand 600 psig (4135 kPa) working refrigerant pressure and
450 psig (3101 kPa) working water pressure. The thermostatic
expansion valve shall provide proper superheat over the entire
liquid temperature range with minimal "hunting." The valve shall
operate bi-directionally without the use of check valves.
Option: Cupro-nickel refrigerant to water heat exchanger shall
be of copper-nickel inner water tube and steel refrigerant outer tube
design, rated to withstand 600 PSIG (4135 kPa) working refrigerant
pressure and 450 PSIG (3101 kPa) working water pressure. Water
lines shall also be of cupronickel construction.
Option: ThermaShield coated water-to-refrigerant heat exchanger,
water lines and refrigerant suction lines shall be insulated to
prevent condensation at low liquid temperatures below 50°F.
Fan Motor and Assembly
The blower shall be a direct drive centrifugal type with a dynamically
balanced wheel. The housing and wheel shall be designed for
quiet, low outlet velocity operation. The blower housing shall be
constructed of galvanized steel and shall be removable from the
unit for servicing of the blower motor. The blower motor shall be a
two-speed PSC or three-speed ECM type and shall be isolated from
the housing by rubber grommets. The motor shall be permanently
lubricated and have thermal overload protection.
Electrical
A control box shall be located within the unit compressor
compartment and shall contain a 75VA transformer, 24 Volt
activated, 2 pole compressor contactor, and solid-state controller
for complete unit operation. Units shall be name-plated for use with
time delay fuses or HACR circuit breakers. Unit controls shall be
24 Volt and provide heating or cooling as required by the remote
thermostat/sensor.
Unit mounted controls shall consist of switches for "OFF", "FAN",
and "AUTO" or "HEAT/COOL". An additional switch is provided for
fan speed setting of "HI" or "LO". The unit shall be equipped with
a fan switch on the side of the control to provide "CONTINUOUS"
or "CYCLED" fan operation. "CYCLED" fan will turn the fan on
with the compressor. A unit-mounted electronic thermostat with a
remote electronic thermistor located in the return air will control
compressor operation in heating and cooling modes.
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RC SERIES ENGINEERING GUIDE