Topics: All categories in the pool
1: Which of the following is an inorganic refrigerant?
- R-22
- Ammonia
- Chlorofluorocarbons
- All of the above
2: Relief valves are rated in
- gallons of water per hour
- pounds of air per hour
- gallons of water per minute
- pounds of air per minute
3: A movie theater would be considered a
- institutional occupancy
- mixed occupancy
- commercial occupancy
- public assembly occupancy
4: Ammonia shall be discharged into ____________ or a tank containing one gallon of water for every pound of ammonia.
- the atmosphere
- a de-pressurized recovery tank with a silver top and yellow bottom
- a tank containing two pounds of a water/lithium bromide mix for every pound of ammonia
- All of the above
5: R-410A is classified as a ____ refrigerant on the safety matrix.
- B-1
- A-1
- B-2
- A-2
6: A compressor that increases vapor pressure by changing the internal volume of the compression chamber is called?
- Pressure induced displacement.
- Positive displacement
- Low Pressure displacement
- Non-positive displacement
7: Refrigerant is metered into the evaporator on a large centrifugal chiller thru the
- low side of the system
- high side float assembly
- cap tube
- none of the above
8: Give an example of a secondary coolant?
- R-12
- R-410A
- R-717
- R-718
9: A water regulating valve opens when
- when the power is on there is an overcharge of refrigerant
- when the power is on
- the head pressure rises
- the compressor is on
10: Control systems can be classified by
- tonnage of system
- safety
- economy of operation
- source of power
11: Pairs of mating stop valves that allow sections of a system to be joined before opening these valves or separated after closing them are
- gate or globe valves
- companion or block valves
- ball valves
- king valves
12: If a halide torch is used for leak detection, what color is the flame if it detects a leak?
- red
- blue
- orange
- green
13: Excessive head pressure is often caused by
- insufficient refrigerant
- leaking reed valve on the discharge side
- air cooled condenser is plugged
- thermostat set too high
14: How many different groups of refrigerants are there?
- 15
- 11
- 7
- 3
15: When this is installed on the high side of a system, it must be capable of reading 1.2 times the design pressure (ASHRAE 15 9.11.3)
- Pressure gauge
- Temperature gauge
- Sight glass gauge
- All of the above
16: Emergency shutdown procedures, including precautions to be observed in case of a breakdown or leak over 55 lbs of refrigerant charge, shall be displayed on a conspicuous card located as near as possible to the
- outside the machinery room
- evaporator
- boiler
- compressor
17: In a motor, an internal overload might open if
- there's an open start winding
- there was a high pressure refrigerant was used for a low pressure system.
- there's a direct short
- there's an excess current draw through the motor
18: A solder joint melts at temperatures of
- 400F to 800F
- 1,200F to 1,500F
- 600F to 900F
- less than 400F
19: A capacitor in series with the start windings will do what?
- Increase starting torque
- Nothing
- Decrease the RLA to within 10% of its rating
- Increase run efficiency by 10% of its rating
20: Adjusting the spring pressure on a TXV
- changes superheat
- changes subcooling
- makes no difference
- adjusts the bulb charge
21: When an electronic bridge is in balance the bridge output will be
- 15 volts
- 0 volts
- 1 volt
- .01 volts
22: R-123 belongs to Group
- B-3
- A-3
- B-2
- B-1
23: What is used to check very low pressure?
- Manometer
- Hygrometer
- Hydrometer
- Velometer
24: The high side float assembly meters refrigerant into the evaporator through the
- lower chamber of the high side
- upper chamber of the low side
- lower chamber of the low side
- upper chamber of the high side
25: Calculate the voltage in a series circuit when the total amperage is 10 amps and the resistors have values of: R1=12 ohms, R2=8 ohms, R3=4 ohms
- 24.0 volts
- 2.40 volts
- 240 volts
- 2,400 volts