Topics: All categories in the pool
1: After setting up a forward curved fan for the desired conditions, something happened to lower the total static pressure the fan had to operate against. Which would occur?
- CFM and HP decrease
- CFM and HP increase
- RPM and CFM increase
- CFM and RPM decrease
2: What should not (and can not) be located between a pressure imposing device and a pressure-limiting device?
- Muffler
- Foot valve
- Moisture indicator
- Stop valve
3: How many CFMs are required per square foot of commercial office occupied space
- 15 CFM
- 20 CFM
- .5 CFM
- 5 CFM
4: The purpose of a receiver is
- a vessel to store refrigerant outside the system
- to increase the capacity that the system can hold
- to use a a later date
- all of the above
5: The main purpose of the accumulator is to
- prevent liquid slugs at the compressor
- store liquid refrigerant
- provide space for the accumulation of oil and containminants
- provide space for vapor to accumulate
6: Which occupancy can ammonia be used in?
- commercial
- depends on the quantity of freon
- redifential
- industrial
7: "I" represents ____ in the Ohm's law formula.
- voltage.
- capacitance
- amperage
- resistance
8: Capacitors are rated in
- volt - amperes
- micro-farads
- megaohms
- kelvins
9: When an inspection is needed, how often must it be done?
- annually
- every 36 months
- every 24 months
- every 18 months
10: Can a R22 line set be reused for a 410A system and if it can be reused, what must be done to it?
- Flush with R-11
- Flush with R-718
- Flush with RX-11
- Flush with ammonia
11: What kind of system uses two different refrigerants in separate systems dependent on each other?
- Simple
- Cascade
- Low pressure
- R-414B
12: What type of oil is used in R-410A systems?
- mineral oil
- polyolester (POE)
- naphthene
- polyalkylene glycol (PAG)
13: Heat that changes the physical state of a substance without effecting a change in its temperature is known as
- latent heat
- specific heat
- sensible heat
- lost heat
14: Ammonia is under what safety classification?
- A3
- B2
- B3
- B1
15: The best way to detect ammonia in brine is
- nessler regaent
- CO2 gas
- carbonation of soda
- potassium of line
16: What type of relief valve is used on a CO2 system?
- glove disc
- fusible plug
- gate valve
- rupture disc
17: How does a centrifugal compressor create the pressure differential needed to move refrigerant through the system?
- Fan-like action
- Rotating vanes
- Nesting scrolls
- Suction and discharge valves
18: Liquid line filter-driers on a 410A system must be rated for no less than
- 400 psig
- 1000 psig
- 200 psig
- 600 psig
19: 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
20: 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
21: A declaration test is needed when the system contains more than
- 120 lbs
- 55 lbs
- 110 lbs
- 65 lbs
22: The start winding has _____ turns than the run winding.
- more
- less
- the same
- none of the above
23: A premise or that portion of a premise where people transact business, receive personal service, or purchase foods, other goods is considered a
- public assembly occupancy.
- business occupancy
- commercial occupancy
- mercantile occupancy
24: R-11 belongs to Group
- A-2
- B-3
- A-1
- B-1
25: In a low temperature refrigeration system, the benefit of the system using P.A.G. oil is
- it is hydroscopic
- it traps moisture
- viscosity
- all of the above