Topics: All categories in the pool
1: Suction valve unloaders afford an effective means of
- evaporator control
- refrigerant control
- capacity control
- superheat control
2: What type refrigerant is NOT ozone depleting?
- HFC
- CFC
- Halon
- HCFC
3: A relief valve shall be located at least ___ above grade.
- 25'
- 36'
- 10'
- 15'
4: "R" represents ___ in the Ohm's law formula
- voltage
- resistance
- amperage
- capacitance
5: The main cause of enacting the "no vending rule" of July 1st 1992 was
- global warming potential
- ozone depletion
- both a & b
- None of the above
6: Pressure is the equivalent of
- force per unit area
- force times area
- area times force
- force
7: When an A/C system is excessively low on refrigerant
- it can become contaminated with water
- there can be nuisance trip outs
- the suction line may be too hot to touch
- All of the above
8: Which is considered the more efficient condenser?
- water cooled
- air cooled
- spray cooled
- fan cooled
9: Bubbles in the liquid line sight glass could be caused by
- overcharge of oil
- bad low pressure switch
- leaking discharge valves in the compressor
- plugged drier
10: Setting a pressure relief device shall not exceed ___ of the design pressure
- 80%
- 75%
- 100%
- 90%
11: What refrigerant has zero ozone depletion
- HFC
- CFC
- HCFC
- None of the above
12: Pressure vessels shall be provided with ___________in accordance with Section VIII of the ASME Boiler & Pressure Vessel Code
- over pressure protection as well as a temperature protection device
- over pressure protection
- Pressure vessels need no type of protection as long as it is hydrostatically tested every three months
- over pressure protection and a rupture disc
13: 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.
14: Ammonia systems use ____ pressure to adjust oil pressure
- air
- discharge
- liquid
- stream
15: Two systems using separate refrigerants that are superimposed upon one another is called
- booster
- cascade
- single stage
- indirect
16: Atmospheric pressure is equal to
- 29.92" Hg
- 14.7 psia
- 14.7 psig
- both a & b
17: Group A1 refrigerants over ____ pounds in a system must discharge to the atmosphere
- 1,000
- 330
- 6.6
- 110
18: What is used to check very low pressure?
- Hydrometer
- Hygrometer
- Velometer
- Manometer
19: Transformers are rated in
- volts
- volt-amps
- amps
- volts-ohms
20: Where are the three places that the discharge from an ammonia relief valve be piped?
- atmosphere, tank containing water, where the A.H.J. indicates
- underground, into drain, into mechanical room
- to chemical neutralizing tank only
- none of the above
21: Before replacing a seized compressor, the _______ should be determinded.
- type of refrigerant
- current draw
- cause of seizure
- designed head pressure
22: A check valve is a device
- designed to allow the flow of refrigerant gas in both directions
- that is always spring loaded
- with a pressure drop
- found on high pressure steam systems
23: How many forces operate a thermostatic expansion valve?
- 3
- 4
- 2
- 1
24: "I" represents ____ in the Ohm's law formula.
- voltage.
- resistance
- capacitance
- amperage
25: How many gallons of water do you need per pound of ammonia?
- 100
- 50
- 1
- 10