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10 Cards in this Set
- Front
- Back
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A system of regularily scheduled inspections and lubrications along with adjustments, minor parts replacement and minor repairs necessary to keep the refrigerating plane and equipment in good operating condition is defined as a) preventative maintenance b) safety controls c) routine operation d) regular maintenance e) predictive maintenance |
a) preventative maintenance |
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What are the causes of reduced air flow which in turn creates an iced up evaporator? (choose all correct answers) a) dirty air filters b) broken fan belt c) high head pressure in condenser d) improperly adjusted fan belt of evaporator e) high temperature of the condenser |
a) dirty air filters b) broken fan belt |
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When some refrigeration systems are to be shut down for a prolonged period of time they should be pumped down and the refrigerant stored in the a) evaporator b) condenser c) receiver d) compressor e) supply cylinders |
c) receiver |
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Which of the following steps is not a step in the start-up of a reciprocating or rotary compressor refrigerating system a) check oil level in the compressor, it should be at or above the center of the sight glass b) check the setting of high and low pressure cut out switches c) open all shutoff valves in the system except bypass valves used elsewhere in the system d) valves in lines connecting suction gauges should be closed e) if the compressor is equipped with an oil sump heater, ensure it is energized and that the oil temperature is high enough to drive off any refrigerant |
d) valves in lines connecting suction gauges should be closed |
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Overcharging the system with refrigerant will create a) the formation of bubbles in the sight glass b) a high discharge pressure condition c) a low pressure suction condition d) the formation of frost at the compressor inlet e) a low oil pressure condition |
b) a high discharge pressure condition |
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To avoid liquid slugging in a direct expansion evaporator after shutting down the reciprocating refrigeration system a) fill the compressor with liquid refrigerant b) fill the evaporator with liquid refrigerant c) pump down the evaporator d) open all the suction valves on the connecting condenser line e) discharge all the condenser refrigerant into the evaporator |
c) pump down the evaporator |
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To start up an older centrifugal refrigeration system the following auxiliary equipment had to be started individually ( choose all correct answers) a) start up the chilled water circulating pump b) start up the condenser cooling water pump c) check the oil level in the chiller d) make sure the king valve is closed e) start up the cooling tower fan |
a) start up the chilled water circulating pump b) start up the condenser cooling water pump e) start up the cooling tower fan |
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When the chilled water temperature rises approx 5-6°C above the cut out point of the control thermostat the a) compressor will be restarted b) compressor will be shut down c) cooling tower fan will be restarted d) cooling tower fan will be shut down e) condenser pump will be restarted |
a) compressor will be restarted |
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If the chilled water temperature drops approx 2.5 to 3°C below the set point of the control thermostat, the chilled water low temperature cut out will a) start the compressor b) shut down the compressor c) start the cooling tower fan d) shut down the cooling tower fan e) start the condenser pump |
b) shut down the compressor |
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If a compressor fails to start but the motor is running, which of the following could be a cause? a) the control circuit is open b) the compressor is seized c) the coupling is sheared or broken d) the motor is burned out e) the starter is defective |
c) the coupling is sheared or broken |
