Carrier 30GB060 - Manual (Page 15)

Guide specifications
1. GENERAL
1.1 Furnish and install complete, factory-assembled
air-cooled reciprocating liquid chiller units of the
type, size and capacity shown on the equipment
schedules. Unit shall be for outdoor use and rated
in accordance with ARI Standard 590 latest edition.
1.2 Equipment schedules and specifications are based
on Carrier Model 30GB060.
1.3 Reciprocating liquid chillers specified in this section
are of the air-cooled single-piece unit packaged type.
1.4 Units shall be of the packaged air-cooled type as
shown on the drawings and consist of a reciprocating
compressor or multiples thereof, direct-expansion
liquid cooler, air-cooled condenser and factory
wiring and piping contained within the unit en­
closure. Unit shall contain a complete operating
charge of refrigerant R-22.
1.5 Unit shall contain factory-installed diagnostic
system, capable of indicating status of all safeties
and energizing remote alarm.
1.6 Unit construction shall comply with ANSI B9.1
safety code, NEC (National Electrical Code) and
ASME Code.
1.7 Unit shall be capable of starting with up to 95 F
(35C) entering water temperature to the cooler.
1.8 Unit shall control leaving water temperature
±_____ ^F (____ ^C) from design point.
1.9 Unit shall be listed with UL.
2. UNIT CASING
2.1 Unit shall be enclosed in a galvanized steel casing,
zinc phosphatized, and coated with a baked enamel
finish, capable of withstanding Federal Test Method
Standard No. 141 (Method 6061) 500-hour salt
spray test.
3. COMPRESSOR
3.1 Each compressor shall be of the reciprocating
serviceable hermetic type only, and shall be
equipped with an automatically reversible oil pump,
operating oil charge, suction and discharge shutoff
valves, and shall be factory mounted on spring
vibration isolators.
3.2 Compressor motor shall be cooled by suction gas
passing around motor winding and shall be thermally
protected. Manual restart shall be required after
stoppage due to thermal and pressure overload.
3.3 Each compressor shall be equipped with an insert
type crankcase heater factory sized to control oil
dilution during shutdown.
3.4 Compressor speed shall not exceed 1750 rpm
(29.2 rps).
4. COOLER
4.1 Cooler shall be shell-and-tube type, with removable
heads. Seamless copper tubes shall be rolled into
tube sheets.
4.2 Cooler shall be tested and stamped in accordance
with ASME code for refrigerant side working
pressure of 235psig (1620 kPa) and a minimum
water side working pressure of 150 psig (1034 kPa).
4.3 Shell shall be insulated with a minimum of 3/4-in.
(19-mm) closed cell polyvinyl chloride (PVC) foam
insulation of maximum K factor 0.28. Heaters along
the shell, under the insulation, shall protect cooler
against freeze-up down to 10 F (-12 C).
4.4 Cooler shall have 2 independent direct-expansion
refrigerant circuits for all models.
5. CONDENSER
5.1 Air-cooled condenser coils shall have aluminum
(copper) fins mechanically bonded to seamless
copper tubes, cleaned, dehydrated, sealed, leak
tested at 150 psig (1034 kPa) and pressure tested
at 450 psig (3103 kPa).
5.2 Condenser fans shall be propeller type with PVC-
coated steel wire safety guards, balanced statically
and dynamically and discharge vertically.
5.3 Condenser fan motors shall have inherent over­
current protection.
6. REFRIGERANT COMPONENTS
6.1 Refrigerant circuit components shall include hot-gas
muffler, high side pressure relief device, liquid-line
shutoff valve, replaceable-core filter drier, moisture
indicating sight glass, and stepper motor actuated
electronic expansion valve (or thermal expansion
valve).
6.2 Expansion valves shall have maximum operating
pressure characteristics to limit inlet suction
pressure.
6.3 If unloaders are to be used, they shall be electrically
actuated suction cutoff cylinder unloaders.
6.4 For 30GB060 units, gages are available as
accessories.
7. CHILLER CONTROLS
7.1 Unit controls, including microprocessor, shall be
factory mounted and wired in a weatherproof
enclosure with hinged access doors for easy access.
Unit shall have automatic lead-lag available with
accessory unloader package. All units shall have
pumpdown at beginning and end of every circuit
cooling cycle, loss-of-charge protection, inherent
low water flow protection, low chilled water tem­
perature safety, low- and high-suction superheat
protection for each circuit. Low oil pressure
protection for each circuit, individual solid-state
compressor protection board and ground current
protection for each compressor are accessories
for 30GB060. Unit shall have low control voltage
to unit, field power and control circuit terminal
blocks, compressor and fan motor circuit breakers,
control circuit breaker, ON/OFF switch, replace­
able relay board, leaving chilled water set point
board, and a diagnostic digital display module, a
microprocessor board, a temperature reset board
(accessory).
7.2 Unit shall control capacity based upon leaving
water temperature and will be compensated by
return water temperature.
7.3 Capaciti! control — Chillers shall have no less
than 4 steps of control.
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