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D-EIMWC01308-16EN - 25/40
Lubrication System
Emkarate RL68H Polyolester Oil must be used in the centrifugal two-stage compressor. The nominal oil
charge for K compressor is 22 gallons.
An internal oil sump is part of the compressor and contains a 750 W submersible fixed-speed oil pump
and a 1.0 kW immersion-type oil heater that is thermostatically controlled. A pre/adjusted oil pressure
regulator valve located in the pump discharge line controls the proper oil pressure to all bearings, gears,
and rotating parts. The oil pump operates prior to start-up and continuously operates during the chiller
operation and coast down.
CAUTION
When
the oil pump operates without any oil or with an
insufficient amount of oil, it might
cause vibration and become extremely noisy and pump damage can occur.
Oil is filtered by an externally mounted 10 micron replaceable cartridge oil filter and is cooled via
refrigerant-cooled oil cooler. Sub-cooled refrigerant liquid is provided by a pressure differential between
the condenser and evaporator to the oil cooler. The supply flow of refrigerant to the oil cooler is
regulated with a thermal expansion valve, by monitoring the temperature of oil coming out of the oil
cooler. Refrigerant leaving the oil cooler is then returned back to the evaporator.
The refrigerant and oil side of the oil cooler are provided with service valves for isolation during service.
WARNING
Comply with local regulations when removing or disposing of refrigerant system oil.
An eductor-based oil recovery system is part of the chiller circuit. It returns oil-rich refrigerant from the
evaporator to the oil sump for separation and reduces or eliminates oil contamination in the evaporator. A
filter drier is installed at the inlet of the eductor.
Both the oil lubrication piping and oil cooler refrigerant piping are completely factory-installed, thus
eliminating the need for any field piping.
Relief Valves
As a safety precaution and to meet applicable pressure vessel code requirements, each chiller is equipped
with spring-loaded pressure relief valves for the purpose of relieving excessive refrigerant pressure
(caused by equipment malfunction, fire, etc.) as noted on the pressure vessel name plate. The relief valve
should be replaced with a new one whenever such a release occurs.
Table 4, Relief Valve Data per Evaporator Circuit
(sized for combined economizer and evaporator)
Evaporator Code
Pressure Setting
Min. Required Discharge Capacity
( lb-air/min )
E4824
200 psi
98
E4826
200 psi
105
E5424
200 psi
108
E5426
200 psi
115
Note :
Calculations based on using an economizer nominal 30 in OD and 64 in Long
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Summary of Contents for WCT
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