Topics: All categories in the pool
1: Which of the following controllers would you expect to be most sensitive to temperature changes?
- low voltage t-stat
- aquastat
- immersion controller
- line voltage t-stat
2: On cooling towers, what causes the condenser water to drop
- ambient temperatures
- tower fans
- sensible heat
- evaporation of the water droplets
3: R22 and 410A operate at the same range of condensing and evaporating temperatures
- true
- false
4: Where a refrigeration or air conditioning system is installed,
- the form or certificate shall be authorized by the Department of Public Safety
- it shall not be operated below prescribed pressuers
- A field inspection shall be made before it is put into service
- The company who installed the system must notify the fire department in the jurisdiction where installed
5: Megaohm meter's main function is
- to detect weak motor winding insulation of a refrigeration or air conditioning compressor by creating high DC voltages to the compressor
- to detect very high resistances to ground of refrigeration or air conditioning compressors
- to test very high value capacitors for large 3-phase refrigeration compressors and blower motors.
- Both a and b are correct
6: What happens to copper joints when overheated?
- nothing
- joint becomes oxidized and ditorted
- copper becomes harder
- none of the above
7: If a condenser is on a roof and the temperature is 35F and dropping the capacity
- increases
- doesn't change
- decreases
- run as designed with low ambient controls
8: The formula for Pure Power in a resistance circuit is
- Watts = volts X amps
- Kw = volts X amps
- Watts X power factor
- Watts X amps.
9: What measures gas pressure?
- Hydrometer
- Hygrometer
- Manometer
- Barometer
10: Start to Run windings will have what resistance?
- All will be at equal values
- The most resistance value
- The least resistance value
- Somewhere between the actual start winding and run winding resistance value
11: In a horizontal shell & tube condenser, the ammonia is liquefied by
- passing thru the tubes from top to bottom
- removing the latent heat of fusion
- water sprayed over condenser
- removing the latent heat of vaporization
12: A High-Probablity system
- is such that a leak of refrigerant from failed connections will enter the occupied space
- is such that any leak will cause injury or death to anyone within a 100 square foot area
- is a system highly likely to leak from a failed connection or component of such system
- is such that a leak of refrigerant from failed connections will enter the unoccupied space
13: A person holding a license as a refrigeration technician may connect or disconnect for the purpose of installation, repair, or replacement, any electrical device or control to be a part of a refrigeration or air conditioning system, from the
- breaker panel in
- first disconnect in
- 24 volt secondary side of the Class 2 transformer to the thermostat
- load-side of the contactor in
14: Evaporators within 18" of a heating coil must be equipped with a
- pressure relief device
- zone valve
- high limit control
- low limit control
15: What should never be used in pressure testing refrigeration systems?
- Oxygen
- Compressed air
- Nitrogen
- Both a and b
16: The maximum permissible amperage draw for a 40VA transfomer with a secondary voltage of 24V is
- 1.2
- .1
- .8
- 1.7
17: The density of a gas refers to
- pounds per cubic foot
- cubic feet per pound
- pounds per square foot
- pounds per absolute pressure
18: Liquid shall not occupy more than ____ of the volume when the temperature of the refrigerant is 90F.
- 100%
- 80%
- 75%
- 90%
19: There can be no airflow from an occupied space through a machine room unless what?
- System is high velocity
- System is ducted and sealed
- Duct is not located in the ceiling
- None of the above.
20: Pi equals approximately
- 3.41
- 3.14
- 12,000
- 746
21: Lithium-bromide, Li-Br, is best characterized as a
- sugar
- salt
- soil
- sand
22: Which of the following is not an air velocity meter?
- Velometer
- Hydrometer
- Anemometer
- Anemotherm
23: In a refrigeration system, you open a valve from the condenser and collect some material on a clean white sheet of bond paper, which of the following would you most likely be testing for?
- checking the level of refrigerant in the system
- testing for oil in the system
- testing for moisture in the system
- none of the above
24: A start capacitor in series with a start winding will
- increase starting torque
- increase the amp draw of the motor
- decrease the amp draw of the motor
- increase running efficiency
25: If the dry bulb temperature is 85F and the wet bulb temperature is 70F, the dew point temperature will be approximately (use psychometric chart)
- 58F
- 77F
- 32F
- 70F