Topics: All categories in the pool
1: Pressure is equivalent of
- Force X Area
- Force
- Area X Force
- Force / Area
2: A crankcase heater has a supplied voltage of 100 volts and is drawing 1.4 amps. What is the resistance?
- 27 ohms
- 104 ohms
- 71 ohms
- 80 ohms
3: An azeotropic refrigerant is
- a mixture of two or more refrigerants that boil at about the same temperature minimizing temperature glide.
- a mixture of two or more refrigerants that boil at much different temperatures causing temperature glide
- a mixture of two or more refrigerants that boil at much different temperatures minimizing temperature glide
- none of the above
4: Booster compressors connect to the ____ side of the compressor
- vapor
- liquid
- oil side
- low side
5: 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
6: 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 of fittings multiplied by 2.31
- the total length of pipe plus equivalent-length of fittings
7: The main purpose of the accumulator is to
- provide space for the accumulation of oil and containminants
- store liquid refrigerant
- provide space for vapor to accumulate
- prevent liquid slugs at the compressor
8: If a halide torch is used for leak detection, what color is the flame if it detects a leak?
- orange
- green
- red
- blue
9: What refrigerant is an inorganic compound?
- R-132A
- R-410A
- R-22
- Ammonia
10: 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
- 240 volts
- 24.0 volts
11: Heat is a form of
- power
- work
- matter
- energy
12: 1 HP = ____ Watts?
- 11,239
- 746
- 3,412
- 3.1416
13: What type of voltage cause a potential relay to open?
- 24 volt supply from the thermostat
- 120 volt line voltage
- Pick-up voltage
- none of the above
14: A motor starter contains a thermal overload and a
- solenoid
- 3-way relay
- transformer
- contactor
15: Materials used in construction and installation materials used in the manufacture or installation of refrigerating equipment shall be suitable for conveying refrigerant and the refrigerant oils and will not deteriorate in the presence of what?
- Moisture and air
- Water and soap
- Oil and water
- Air and dirt
16: An air conditioning system rated for 36,000 BTU's is equivalent to
- one ton of cooling
- two tons of cooling
- 12,000 tons of cooling
- three tons of cooling
17: Ammonia systems use ____ pressure to adjust oil pressure
- stream
- air
- discharge
- liquid
18: Capacity control on a centrifugal compressor is accomplished by the
- check valves
- pre-rotational guide vanes
- post-rotational guide vanes
- slide vanes
19: Defined process piping by code CMR (528)
- Any piping that conveys a solid, liquid or gas that is not part of the plumbing or fire protection system
- Any piping in an industrial space
- Any piping in an industrial or commercial space
- All of the above
20: 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
21: Crankcase heaters are energized
- to prevent compressor freeze-up
- while the compressor is running
- to allow easy compressor start-up
- when the compressor is off
22: Liquid line filter-driers on a 410A system must be rated for no less than
- 600 psig
- 400 psig
- 1000 psig
- 200 psig
23: Which occupancy can ammonia be used in?
- depends on the quantity of freon
- industrial
- redifential
- commercial
24: The two basic types of evaporators are
- prime surface and finned
- finned and plate
- flooded and direct expansion
- direct expansion and plate
25: How many flammability classifications are refrigerants in?
- 5
- 7
- 3
- 2