Topics: All categories in the pool
1: Liquid refrigerant flashing, or turning to vapor, in the liquid line may be due to
- liquid line that is too small
- shortage of refrigerant
- liquid line that had too high vertical lift
- All of the above
2: Low ambient controls are used when
- always
- on air conditioning systems only
- when systems run all year round
- economizers are used
3: How many BTU's is produced by one watt of energy
- 1
- 2.57
- 3.41
- 3.00
4: Class A refrigerants are considered
- non-flammable
- toxic
- flammable
- non-toxic
5: How many gallons of water per pound of ammonia do you need?
- 15
- 5
- 20
- 1
6: Ammonia systems use ____ pressure to adjust oil pressure
- discharge
- air
- stream
- liquid
7: Class 3 refrigerants are
- non-toxic
- highly flammable
- toxic
- non-flammable
8: On cooling towers, what causes the condenser water to drop
- tower fans
- evaporation of the water droplets
- ambient temperatures
- sensible heat
9: 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.
10: Joints in piping for refrigeration containing parts must withstand temperatures of ___?
- 1000F
- 800F
- 600F
- 700F
11: One ton of refrigeration is defined as ______ btu/minute.
- 720,000
- 60
- 12,000
- 200
12: The high side float assembly meters refrigerant into the evaporator through the
- lower chamber of the low side
- upper chamber of the high side
- lower chamber of the high side
- upper chamber of the low side
13: Pressure vessels of 10 cubic feet or more gross volume shall use
- at least one rupture member
- a dual pressure-relief valve if charging into the atmosphere
- at least three means of discharge and/or rupture discs
- both a and b are correct
14: Pressure is equivalent of
- Force
- Force / Area
- Force X Area
- Area X Force
15: A motor starter is a device that includes an overload and a _______?
- contactor
- 2-pole contacts
- duel-coil
- all of the above
16: The amount of heat required to raise the temperature of 1 lb of water 1F is?
- The rate of conduction
- 1 BTU
- 1 Kelvin
- 1 Therm
17: Name a reason that does not cause reduced condenser air quantity
- Dirty Coil
- Dirty fan blades
- Prevailing winds
- High ambient temperature
18: Capacity control on an absorption system is typically accomplished by varying the
- rate at which heat is supplied to the generator
- speed of the chilled water circulatory pump
- pressure setting on the system's rupture disc
- speed of the condenser water circulator pump
19: What type of oil is used in R-410A systems?
- polyolester (POE)
- naphthene
- polyalkylene glycol (PAG)
- mineral oil
20: An oil pressure safety switch should be set at
- 5 to 10 psi below low side pressure
- 10-15 psi above low side pressure
- 5 to 10 psi above low side pressure
- 10 to 15 psi below low side pressure
21: The External equalizer of a TXV compensates for
- pressure within the evaporator
- pressure within the system
- pressure drop across the evaporator coil
- pressure drop across the condenser coil
22: Which is considered the more efficient condenser?
- air cooled
- fan cooled
- spray cooled
- water cooled
23: Crankcase heaters are energized
- when the compressor is off
- while the compressor is running
- to allow easy compressor start-up
- to prevent compressor freeze-up
24: If your suction line is warmer than the room temperature, this may indicate
- plugged air filter
- below normal superheat
- a low charge
- an over charge
25: Who authorizes changes to the safety codes?
- Person in charge of the facility
- Person who pulled the permit
- Contractor who last serviced the system.
- Board of Boilers