Topics: All categories in the pool
1: The instrument used to measure the specific gravity of absorption chiller solutions is the
- Psychrometer
- anemometer
- refractometer
- hydrometer
2: Which has more turns in the windings: Start windings or Run windings?
- Start windings
- Run windings
- They both have the exact same turns
- Depends on the system and capacitor used
3: On a centrifugal compressor, stationary diffuser vanes are needed to
- increase the clearance space
- stop gas flow
- prevent high pressure on the packing
- convert velocity energy to pressure
4: How many BTU's is produced by one watt of energy
- 3.41
- 3.00
- 1
- 2.57
5: When systems are protected by a high pressure relief device, the compressor's pressure limiting device shall be set at or below ____ % of the operating pressure of the high side relief device.
- 80
- 100
- 90
- 110
6: What should not (and can not) be located between a pressure imposing device and a pressure-limiting device?
- Muffler
- Moisture indicator
- Foot valve
- Stop valve
7: If a purge unit fails on a low pressure chiller, what are the symptoms?
- low pressure chillers do not have purge units
- high head pressure
- increased capacity
- low suction pressure
8: What refrigerant doesn't have to be classifted?
- R-717
- R-134a
- R-718
- R-711
9: Before replacing a seized compressor, the _______ should be determinded.
- type of refrigerant
- cause of seizure
- current draw
- designed head pressure
10: The density of a gas refers to
- cubic feet per pound
- pounds per square foot
- pounds per cubic foot
- pounds per absolute pressure
11: What is not a requirement of a Class T machine room?
- Fire hose connected to the building fire protection system.
- Tight fitting doors
- Automatic ventilation
- Self-closing doors
12: The critical temperature of a refrigerant gas occurs when
- the gas is no longer saturated
- any decrease in pressure will cause condensation
- the gas returns to a liquid
- any increase in pressure will not liquefy the gas
13: A high side float is a
- float type valve that controls the amount of refrigerant stored in the receiver
- float type valve that controls the crankcase oil level
- metering device used on critically charged systems that controls the level of the liquid refrigerant in the high pressure side of the system.
- float type switch that stops the compressor when the pressure on the high side becomes too high
14: RPM's of a centrifugal compressor are at approximately?
- 15,000
- 10,000
- 500
- 30,000
15: Fractionation occurs when
- when a fraction of refrigerant is added as the full charge
- some of the blended refrigerant evaporates or condenses before the rest of the blend
- the pressures decreases as the heat load decreases
- the pressures increase as the heat load increases
16: A motor is rated for 120 volts and has a RLA (rated-load amps) of 5 amps. What is the wattage of the motor?
- 5KW
- 746 watts
- 1000 watts
- 600 watts
17: What would be the classification of a church?
- Industrial
- Large mercantile
- Place of assembly
- Institutional
18: When an inspection is needed, how often must it be done?
- every 24 months
- every 18 months
- annually
- every 36 months
19: "I" represents ____ in the Ohm's law formula.
- voltage.
- resistance
- capacitance
- amperage
20: Low ambient controls are used when
- economizers are used
- when systems run all year round
- always
- on air conditioning systems only
21: Large mercantile occupancy is
- a premise or that portion of a premise where more than 200 persons congregate on levels above or below street level to purchase personal merchandise
- a premise of that portion of a premise where more than 50 persons congregate on levels above of below street level to purchase personal merchandise.
- a premise of that portion of a premise where more than 100 persons congregate on levels above of below street level to purchase personal merchandise.
- a premise or that portion of a premise where more than 1500 persons congregate on levels above or below street level to purchase personal merchandise
22: A EPR valve is installed on what type of evaporators?
- low-temperature evaporators
- high-temperature evaporators
- shell and tube evaporators
- plate evaporators
23: Relief valves are rated in
- gallons of water per hour
- gallons of water per minute
- pounds of air per hour
- pounds of air per minute
24: Doors communicating with outside from a mechanical room must be?
- Self-closing, aligned, fire door
- Self-closing, wooden, fire door
- Steel, approved, weather-stripped
- Self-closing, approved, fire door
25: Brazed joints melt at temperatures above
- 1,000F
- 800F
- 1,200F
- 500F