Topics: All categories in the pool
1: A chilled water pump's suction gauge reads 10 psig. The discharge gauge reads 48 psig. What is the head in feet the pump is working against?
- 96
- 88
- 38
- 58
2: If a low-pressure chiller has a low-side leak, which of the following will most likely result?
- High head pressure and low suction pressure
- Low suction pressure and low discharge pressure
- Low head pressure and high suction pressure
- High suction pressure and high discharge pressure.
3: The density of a gas refers to
- pounds per cubic foot
- cubic feet per pound
- pounds per absolute pressure
- pounds per square foot
4: Class A refrigerants are considered
- non-flammable
- non-toxic
- toxic
- flammable
5: R22 and 410A operate at the same range of condensing and evaporating temperatures
- true
- false
6: Pressure vessels with an internal volume of 3 cubic feet or less
- do not need pressure relief protection
- shall use fusible plugs
- shall use pressure relief devices or fusible plugs
- shall use pressure relief devices
7: The rupture disc on a low-pressure chiller typically releases pressure at
- 0 psig
- 15 psig
- 10 psig
- 5 psig
8: The 522 CMR 9.00 has adopted for reference ASHRAE ____
- III
- 25
- 10
- 15
9: The test pressure applied to the high side of each factory-assembled refrigerating system shall be at least equal to the design pressure of
- the aggregate of the high side and low side
- the high side
- 2.5 times the design pressure
- the low side
10: Lithium-bromide, Li-Br, is best characterized as a
- sugar
- salt
- sand
- soil
11: A room having machinery but no flame producing apparatus permanently installed and operated is considered a
- Class T machinery room
- Class B machinery room
- Class M machinery room
- Class A machinery room
12: Most CFC's are
- toxic
- inert
- inert but toxic
- flammable
13: In a horizontal shell & tube condenser, the ammonia is liquefied by
- water sprayed over condenser
- removing the latent heat of vaporization
- passing thru the tubes from top to bottom
- removing the latent heat of fusion
14: What are the three components of a transformer?
- Contacts, secondary coil, and core
- Primary coil, secondary coil, and copper contacts
- Primary coil, secondary coil, and core
- Primary core, secondary coil, and high and low voltage connectors.
15: Two capacitors are wired in parallel. One capacitor has a value of 15uf. The other has a value of 25uf. What is the total value supplied?
- 40 uf
- 25 uf
- 20 uf
- 15 uf
16: 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
17: R-12. R-22, and R-40 are considered Group I refrigerants.
- True
- False
18: How far from the ground does a relief valve need to be?
- Not more than 3' above grade
- At least 20' above grade
- At least 15' above grade
- At least 25' above grade
19: Which has more turns in the windings: Start windings or Run windings?
- Start windings
- Run windings
- They both have the exact same turns
- Depends on the system and capacitor used
20: How are a compressor and condenser fan wired?
- parallel
- series-parallel
- series
- parallel-series
21: Megaohm meters can detect a ground in the
- 10,000,000 ohms or higher
- up to 1,000,000 ohms
- up to 1,000 ohms
- up to 10,000 ohms
22: How many groups of refrigerants are there?
- 5
- 7
- 3
- 1
23: What is not a requirement of a Class T machine room?
- Self-closing doors
- Automatic ventilation
- Fire hose connected to the building fire protection system.
- Tight fitting doors
24: If a purge unit fails on a low pressure chiller, what are the symptoms?
- low pressure chillers do not have purge units
- increased capacity
- low suction pressure
- high head pressure
25: A declaration test is needed when the system contains more than
- 120 lbs
- 65 lbs
- 55 lbs
- 110 lbs