Topics: All categories in the pool
1: A single pole-double throw switch uses how many wires?(excluding the ground)
- 2
- 3
- 5
- 4
2: A pressure-limiting device isn't required on a factory-sealed system containing less than ____ lbs.
- 50
- 66
- 25
- 22
3: What type of copper is not permitted on refrigeration systems?
- Type N
- Type K
- Type M
- Type L
4: Before replacing a seized compressor, the _______ should be determinded.
- designed head pressure
- cause of seizure
- current draw
- type of refrigerant
5: Systems containing more than 110 pounds must have stop valves located at the
- compressor suction inlet
- compressor discharge outlet
- receiver inlet and outlet
- All of the above
6: How far from the ground does a relief valve need to be?
- At least 15' above grade
- Not more than 3' above grade
- At least 25' above grade
- At least 20' above grade
7: Heat that changes the physical state of a substance without effecting a change in its temperature is known as
- sensible heat
- lost heat
- specific heat
- latent heat
8: A professional or office building would be considered what type of occupancy?
- mercantile
- public assembly
- business
- commercial
9: Pressure vessels with an internal volume of 3 cubic feet or more
- shall use fusible plugs
- shall use pressure relief devices
- do not need pressure relief protection
- shall use pressure relief devices or fusible plugs
10: When can recovered refrigerants be reused?
- They can't
- Only when used in original owner's equipment
- Only if used in 30 days of recovery
- None of the above
11: A premise or that portion of a premise where people transact business, receive personal service, or purchase foods, other goods is considered a
- commercial occupancy
- public assembly occupancy.
- mercantile occupancy
- business occupancy
12: 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
13: All machine rooms must be outfitted with a detector that _______?
- activates an audible alarm
- activates a visual alarm
- starts the ventilation system
- All of the above
14: A total of all group A-2,B-2, A-3, and B-3 refrigerants shall not exceed ____ lb in the occupied areas and machinery rooms of institutional occupancies.
- 100
- 50
- 350
- 550
15: A machine room with a refrigerant system using ammonia shall
- be provided with a continuously operated ventilation system
- be considered a non-hazardous location in accordance with National Electrical code
- have no flame producing apparatus permanently installed and operated
- All of the above
16: Cooling tower lowers condenser water temp by
- running water thru a secondary heat exchanger
- condensation
- evaporative cooling
- running fans at 100%
17: A secondary coolant is defined as
- any liquid used for the transmission of heat without a change of state in A/C refrigeration systems having flash point above 150F
- any refrigerant direcly in contact with the cooling space for process cooling
- a combination of interconnected parts from a closed circuit in where fluid is circulated for the purpose of cooling for a refrigeration system.
- a low temperature refrigerant used for cascading systems
18: Instead of using a compressor, an absorption air-conditioning chiller uses which of the following as its driving force?
- Electricity
- Air
- Heat
- Oil
19: The Board of Boilers adopts by reference
- Montreal Protocol Safety Code
- the 1997 ANSI/ASHRAE Safety Code
- the MACS Pressure Vessel Code of Massachusetts
- MSCA Code
20: Absolute pressure is
- Gauge Pressure
- Atmospheric Pressure
- Gauge + Atmospheric Pressure + Pi
- none of the above
21: Sensible heat is the heat added to a substance to
- change its state
- cause evaporation
- raise its temperature
- freeze it
22: 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
23: Which refrigerant(s) is an HFC?
- R-22
- R-410A
- R-502
- All of the above
24: What's the purpose of a megohmmeter?
- To measure low to very low resistance values
- To alternate the current in a DC circuit in order to calculate the total impedance of a circuit
- To measure very high resistances
- None of the above
25: On cooling towers, what causes the condenser water to drop
- tower fans
- ambient temperatures
- sensible heat
- evaporation of the water droplets