Topics: All categories in the pool
1: Which of the following is an inorganic refrigerant?
- R-22
- Ammonia
- Chlorofluorocarbons
- All of the above
2: 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
- 2,400 volts
- 2.40 volts
- 24.0 volts
- 240 volts
3: What type of relief valve is used on a CO2 system?
- rupture disc
- gate valve
- fusible plug
- glove disc
4: Crankcase heaters are energized
- while the compressor is running
- to prevent compressor freeze-up
- to allow easy compressor start-up
- when the compressor is off
5: Two capacitors are wired in parallel. One capacitor has a value of 15uf. The other has a value of 25uf. What is the total value supplied?
- 20 uf
- 25 uf
- 40 uf
- 15 uf
6: On cooling towers, what causes the condenser water to drop
- ambient temperatures
- evaporation of the water droplets
- tower fans
- sensible heat
7: If a purge unit fails on a low pressure chiller, what are the symptoms?
- increased capacity
- low pressure chillers do not have purge units
- high head pressure
- low suction pressure
8: When an inspection is needed, how often must it be done?
- every 18 months
- every 24 months
- annually
- every 36 months
9: Pressure is the equivalent of
- force per unit area
- area times force
- force times area
- force
10: What is potential measured in?
- Henrys
- Volts
- Ohms
- Amps
11: Direct systems using Group II refrigerants
- shall be installed per instruction of the AHJ
- shall be installed in Class T machinery rooms
- shall be allowed to be used for human comfort.
- shall not be used for air condition for human comfort
12: How do you find net oil pressure on a compressor?
- discharge pressure - suction pressure
- gross oil pressure - suction pressure
- gross oil pressure - discharge pressure
- all of the above
13: Control systems can be classified by
- source of power
- safety
- economy of operation
- tonnage of system
14: What refrigerant doesn't have to be classified?
- R-717
- R-422A
- R-134A
- R-718
15: Pressure vessels shall be provided with ___________in accordance with Section VIII of the ASME Boiler & Pressure Vessel Code
- Pressure vessels need no type of protection as long as it is hydrostatically tested every three months
- over pressure protection as well as a temperature protection device
- over pressure protection
- over pressure protection and a rupture disc
16: Liquid line filter-driers on a 410A system must be rated for no less than
- 400 psig
- 600 psig
- 1000 psig
- 200 psig
17: Indirect systems using Group II refrigerants
- shall be used in refrigeration system less than 1,000 lbs
- shall be used for mechanical equipment only
- shall be used in refrigeration system in excess of 1,000 lbs
- shall have all refrigerant containing parts except piping, installed in a Class T machine room
18: At higher altitudes, boiling temperatures
- decrease
- depends on the refrigerant
- increase
- are unaffected
19: The equivalent length of pipe in a water piping system is
- the total length of pipe as you would measure it
- the total length of pipe as you would measure it plus 25% for fittigns
- the total length of pipe plus equivalent-length of fittings
- the total length of pipe plus equivalent of fittings multiplied by 2.31
20: What is used to check very low air pressures in air conditioning duct?
- Manometer
- Barometer
- Vacuum gauge
- Anemomter
21: What is considered a cooling agent?
- any liquid used for the transmission of heat without vaporization
- any liquid used for the transmission of heat when vaporization occurs
- any liquid used for the transmission of heat without condensation
- any liquid used for the transmission of heat when condensation occur
22: On an air cooled condenser, if the ambient air is 35F and dropping, what's its effect to the condensor?
- it would make the condenser more efficient
- it would make the condenser less efficient
- it would cause the condenser to sweat
- it would have no effect on the condenser
23: If a halide torch is used for leak detection, what color is the flame if it detects a leak?
- green
- red
- orange
- blue
24: E = I X R is
- Ohms Law
- Amps Law
- Impedance Law
- Watts Law
25: What would be the classification of a church?
- Large mercantile
- Place of assembly
- Institutional
- Industrial