Topics: All categories in the pool
1: B3 refrigerants are considered
- toxic and highly flammable
- toxic but non-flammable
- non-toxic but flammable
- non-toxic but non-flammable
2: If a halide torch is used for leak detection, what color is the flame if it detects a leak?
- red
- orange
- blue
- green
3: What is the boiling point of refrigerant governed by?
- Condenser sub-cooling
- Evaporator temperature
- P&T relationship
- Compressor RPM's
4: Which of the following is NOT a positive displacement compressor?
- centrifugal
- scroll
- reciprocating
- screw
5: On a large centrifugal system, what meters the flow to the evaporator?
- TXV
- High side float
- Low side float
- Cap tube.
6: Fusible plugs must have what marked on them?
- Melting temperature in F
- Melting temperature in C
- Opening pressure
- All of the above
7: "R" represents ___ in the Ohm's law formula
- resistance
- capacitance
- amperage
- voltage
8: When can 50/50 solder be used?
- in the low side
- in the high side
- liquid and suction lines
- none of the above.
9: Cooling tower lowers condenser water temp by
- condensation
- evaporative cooling
- running water thru a secondary heat exchanger
- running fans at 100%
10: The principle used in continuous type absorption systems is
- Dalton's Law
- Ohm's Law
- Boyle's Law
- Charles's Law
11: How many gallons of water per pound of ammonia do you need?
- 1
- 5
- 15
- 20
12: All electrical work done on refrigeration systems must comply with
- ASHREA-15 Section 9.2.1
- OSHA
- NEC and Massachusetts Modifications
- Department of Energy
13: The Department that certifies the transportation of refrigerant is the
- EPA
- EPO
- RSES
- DOT
14: Dew point is
- the temperature below which water vapor in the air will start to evaporate
- the temperature above which water vapor in the air will start to condense
- the temperature of air of 50% RH
- the temperature below which water vapor in the air will start to condense
15: A 50 VA control transformer with a 25 volt control output would be rated for _________ amps.
- There isn't enough information to answer.
- 2.5
- 1250
- 2
16: Sublimation occurs when
- liquid is formed from a gas
- ice melts and turns to water
- gas is formed from a liquid
- gas is formed directly from a solid
17: The best way to determine the voltage requirement for an electrical component is to
- read the nameplate data
- read the voltage with a mulitmeter
- check with the utility company
- determine the capacity of the service panel
18: Liquid level gauges must be provided with what?
- A red line
- A low level mark
- Automatic shut-offs
- A relief valve
19: If the power element on an expansion valve should lose its charge, the valve would
- Under feed
- Stay open
- Close
- Over feed
20: An oil pressure safety switch should be set at
- 5 to 10 psi above low side pressure
- 10 to 15 psi below low side pressure
- 5 to 10 psi below low side pressure
- 10-15 psi above low side pressure
21: A solder joint melts at temperatures of
- less than 400F
- 400F to 800F
- 1,200F to 1,500F
- 600F to 900F
22: Name a reason that does not cause reduced condenser air quantity
- Dirty fan blades
- High ambient temperature
- Prevailing winds
- Dirty Coil
23: According to the 522 CMR Board of Boilers, refrigerant detectors, alarms, and the refrigeration mechanical room ventilating systems shall be tested
- regularly
- annually
- quarterly
- bi-annually
24: A motor is rated for 120 volts and has a RLA (rated-load amps) of 5 amps. What is the wattage of the motor?
- 600 watts
- 5KW
- 1000 watts
- 746 watts
25: Halo-carbon refrigerants cannot be used with what material?
- Stainless Steel
- Magnesium alloy
- Aluminum
- Copper