Topics: All categories in the pool
1: The freezing point of water at sea level is?
- -10C
- 32F
- 32C
- 0F
2: On a pumpdown system, the liquid-line solenoid is controlled by the
- low pressure switch
- thermostat
- low-ambient controller
- defrost timer
3: In a horizontal shell & tube condenser, the ammonia is liquefied by
- removing the latent heat of vaporization
- passing thru the tubes from top to bottom
- removing the latent heat of fusion
- water sprayed over condenser
4: Before replacing a seized compressor, the _______ should be determinded.
- designed head pressure
- current draw
- cause of seizure
- type of refrigerant
5: A class B1 refrigerant is considered
- toxic and somewhat flammable
- non-toxic but highly flammable
- non-toxic and non-flammable
- toxic but non-flammable
6: What type of voltage causes the winding in a potential relay to open?
- BEMF (Back Electro-Motive Force)
- 24V control voltage from the thermostat
- 120V line voltage
- None of the above
7: Lithium-bromide, Li-Br, is best characterized as a
- sugar
- sand
- soil
- salt
8: Thermodynamics is the branch of science that deals with
- state of energy
- heat energy
- energy due to motion
- molecular therory
9: The high side float assembly meters refrigerant into the evaporator through the
- lower chamber of the low side
- upper chamber of the low side
- lower chamber of the high side
- upper chamber of the high side
10: What type of copper is not permitted on refrigeration systems?
- Type M
- Type N
- Type K
- Type L
11: Refrigerant piping crossing an open space that affords passageway in any building shall not be less than _____ feet above the floor unless piping is located against the ceiling.
- 7.25'
- 9.00'
- 8'4"
- 7.00'
12: Capacitors are rated in
- volt - amperes
- megaohms
- kelvins
- micro-farads
13: How would you know if there was a loss of crankcase pressure?
- oil will thin out
- oil will thicken
- oil will foam
- oil level will rise
14: On a 460V motor, what is he MAXIMUM voltage that can be safely applied to it?
- 506v
- 550v
- 660v
- None of the above
15: What should not (and can not) be located between a pressure imposing device and a pressure-limiting device?
- Moisture indicator
- Stop valve
- Muffler
- Foot valve
16: What is used to check very low pressure?
- Hygrometer
- Manometer
- Velometer
- Hydrometer
17: The rupture disc on a low-pressure chiller typically releases pressure at
- 15 psig
- 5 psig
- 0 psig
- 10 psig
18: Which occupancy can ammonia be used in?
- redifential
- depends on the quantity of freon
- industrial
- commercial
19: The actual expansion curve of compressor follows most nearly which one of the following
- Pressure-Temperature
- Isothermal
- Volume
- Adiabatic
20: What must be done to refrigerant pipes before being buried ?(8.10.4)
- Certified
- Classifed
- Leak checked
- Insulated and installed in a pipe duct (Encased)
21: Group A1 refrigerants over ____ pounds in a system must discharge to the atmosphere
- 330
- 1,000
- 6.6
- 110
22: How many gallons of water do you need per pound of ammonia?
- 50
- 100
- 10
- 1
23: When systems are protected by a high pressure relief device, the compressor's pressure limiting device shall be set at or below ____ % of the operating pressure of the high side relief device.
- 110
- 100
- 80
- 90
24: How many flammability classifications are refrigerants in?
- 2
- 7
- 5
- 3
25: Pipe identification labels are required when the system contains more than
- 65 lbs
- 120 lbs
- 110 lbs
- 55 lbs