Topics: All categories in the pool
1: Ohm's Law indicates Amps X Resistance = ___________.
- Volts
- Current
- Ohms
- Impedance
2: What is the refrigerant dichlorodifluoromethane?
- R-134A
- R-22
- R-123
- R-12
3: R-11 has the greatest corrosive effect on
- Bronze
- Aluminum
- Copper
- Magnesium
4: Laten heat is associated with a change in state of a refrigerant but not temperature
- True
- False
5: Indirect systems using Group II refrigerants
- shall have all refrigerant containing parts except piping, installed in a Class T machine room
- shall be used in refrigeration system in excess of 1,000 lbs
- shall be used in refrigeration system less than 1,000 lbs
- shall be used for mechanical equipment only
6: Clearance volume
- affects compressor capacity
- varies depending on compressor speed
- has no effect on compressor capacity
- is the same on all compressors
7: What type of fuses must be used on a HVAC system?
- TR Type, Duel Element, Time Delay
- Fast blow
- 10% lower than RLA
- none of the above
8: The total amount of refrigerant stored in a machinery room in all containers not provided with relief valves shall not exceed
- 330 lbs
- 660 lbs
- 500 lbs
- 55 lbs
9: The ASHRAE Standard 34 requires what type of alarm for equipment rooms using HCFC-123?
- phosgene gas sening
- refrigerant sensing
- CO Sensing
- A group sensing
10: The oil separator is always inserted in the system
- in the discharge line
- where it can be easily serviced
- to prevent oil logging
- in a cool spot
11: At higher altitudes, boiling temperatures
- increase
- are unaffected
- depends on the refrigerant
- decrease
12: Gauge pressure is
- Barometric pressure
- Atmospheric pressure
- Force of pressure above that of atmosphere
- Absolute pressrue
13: Usually dry bulb temperature is
- lower than dry bulb temperature
- same as wet bulb temperature
- higher than wet bulb temperature
- not important and shall be ignored
14: If a refrigerant leaving the condenser is 94F and the condensing temperature is 105F, the subcooling is
- 11F
- 9F
- 21F
- 29F
15: When can 50/50 solder be used?
- in the low side
- in the high side
- liquid and suction lines
- none of the above.
16: While the system is operating, the discharge line should be
- room temperature
- too hot to hold by hand
- 10-15F warmer than ambient
- at the same temperature as the crankcase
17: Refrigerant restricted in 2004 but used for transition for decades:
- R-134A
- R-22
- R-11
- R-123
18: Fractionation occurs when
- the pressures increase as the heat load increases
- some of the blended refrigerant evaporates or condenses before the rest of the blend
- the pressures decreases as the heat load decreases
- when a fraction of refrigerant is added as the full charge
19: Whoever owns/uses a refrigeration or air conditioning system covered by this code
- must notify the Department of Public Safety prior to starting the system
- shall be licensed by the Commonwealth of Massachusetts according to CMR 522
- shall make application for inspections to the Chief of Inspectors
- None of the above
20: Group A3 refrigerants have a ______ flammability rating than Group B1 refrigerants
- lower
- there is no Group B1 refrigerants
- higher
- the same
21: Relief valves are rated in
- pounds of air per hour
- pounds of air per minute
- gallons of water per minute
- gallons of water per hour
22: Dual-pressure relief devices should be installed on
- vessels of 10 cubic feet or less
- vessels of 3 cubic feet or more
- vessels of 3 cubic feet or less
- vessels of 10 cubic feet or more
23: What is a megaohm meter?
- An electric meter that measures very high resistance values by sending a high DC voltage signal into the object being tested
- Is an electric meter that measures extremely low resistance valves by sending high DC voltage signal into the object being tested.
- An electric meter used by electricians to test large 3-phase blower motors for the correct rotation
- An electric meter that measures very high resistance values by sending a low voltage AC signal into the object being tested
24: Joints in refrigeration piping must be _____ before being covered?
- Insulated
- Inspected
- Leak tested
- Pressurized
25: Where is an EPR valve located on a multi-evaporator system?
- Suction line at the compressor
- Suction line of the coolest evaporator
- Suction line of the warmest evaporator
- Suction line prior to the accumulator of the lowest temperature system