a. Oil pump with factory-installed motor contactor with overload protection.
b. Oil pressure sensor with differential readout at main control center.
c. Oil pressure regulator.
d. Oil filter with isolation valves to allow filter change without removal of refrigerant charge.
e. Oil sump heater [115 v, 50 or 60 Hz] controlled from unit microprocessor.
f. Oil reservoir temperature sensor with main control center digital readout.
g. All wiring to oil pump, oil heater, and controls shall be pre-wired in the factory and power shall be applied to check proper operation prior to shipment.
7. Compressor shall be fully field serviceable. Compressors that must be removed and returned to the factory for service shall be unacceptable.
8. Acoustical attenuation shall be provided as required, to achieve a maximum (full load or part load) sound level, measured per ARI Standard 575 (latest edition).
1. Compressor motor shall be of the semi-hermetic, liquid refrigerant cooled, squirrel cage, induction type suitable for voltage shown on the equipment schedule.
2. If an open (air cooled) motor is provided, a compressor shaft seal leakage containment system shall be provided:
a. An oil reservoir shall collect oil and refrigerant that leaks past the seal.
b. A float device shall be provided to open when the reservoir is full, directing the refrigerant/oil mixture back into the compressor housing.
c. A refrigerant sensor shall be located next to the open drive seal to detect leaks.
3. Motors shall be suitable for operation in a refrigerant atmosphere and shall be cooled by atomized refrigerant in contact with the motor windings.
4. Motor stator shall be arranged for service or removal with only minor compressor disassembly and without removing main refrigerant piping connections.
5. Full load operation of the motor shall not exceed nameplate rating.
6. One motor winding temperature sensor (and on spare) shall be provided.
7. Should the mechanical contractor choose to provide a chiller with an air-cooled motor instead of the specified semi-hermetic motor, the contractor shall install additional cooling the following formula:
Btuh = (FLkW motor) (0.05) (3413)
Btuh = (FLkW motor) (171)
Tons = Btuh/12,000
The additional piping, valves, air-handling equipment, insulation, wiring, switchgear changes, ductwork, and coordination with other trades shall be the responsibility of the mechanical contractor. Shop drawings reflecting any changes to the design shall be included in the submittal, and incorporated into the final as-built drawings for the project.
8. Also, if an open motor is provided, a mechanical room thermostat shall be provided and set at 104 F (40 C). If this temperature is exceeded, the chillers shall shut down and an alarm signal shall be generated to the central Energy Management System (EMS) display module, prompting the service personnel to diagnose and repair the cause of the overtemperature condition. The mechanical contractor shall be responsible for all changes to the design, including coordination with temperature control, electrical and other trades. In addition, the electrical power consumption of any auxiliary ventilation and/or mechanical cooling required to maintain the mechanical room conditions stated above shall be considered in the determination of conformance to the scheduled chiller energy efficiency requirement.
D. Unit-Mounted Variable Frequency Drive (VFD) with Built-In Harmonic LiquiFlo™ II Filter:
The compressor shall be factory-mounted, factory-wired and factory-tested prior to shipment by the chiller manufacturer. All interconnecting wiring and piping between the VFD and the chiller shall be factory-installed. Customer electrical connection for compressor motor power shall be limited to main power leads to the VFD, and wiring liquid pumps and tower fans to the chiller control circuit. The VFD shall incorporate the