Topics: All categories in the pool
1: Most CFC's are
- inert but toxic
- flammable
- toxic
- inert
2: Pressure vessel having an inside diameter exceeding 6” with an internal pressure greater than 15psig shall be marked directly on or on the nameplate the letters _______________ signifying compliance with the ASME Boiler & Pressure Vessel Code.
- “UL”
- “UV”
- “U” or “UM”
- “UM” and “UV”
3: Electricity involves the movement of electrons in atoms
- True
- False
4: A High-Probability System
- is a system highly likely to leak form a failed connection or component of such system
- is such that a leak of refrigerant from a failed connection will enter an unoccupied space
- is such that any leak will cause injury or death to anyone within a 100 square foot area
- is such that a leak of refrigerant from a failed connection will enter the occupied space
5: On a ammonia compressor, the pressure of a forced fed oil pump is changed by varying the
- adjustment of the spring tension of the TXV
- cooling temperature set-point
- opening at the pump inlet
- opening at the pump outlet
6: Setting a pressure relief device shall not exceed ___ of the design pressure
- 75%
- 80%
- 90%
- 100%
7: Class A refrigerants are considered
- non-flammable
- toxic
- non-toxic
- flammable
8: What type of refrigerants are NOT flammable?
- CHC
- HFC
- HCFC
- All of the above
9: Pressure-limiting device isn't required on a factory-sealed system containing less than ____ lbs.
- 50
- 22
- 33
- 18
10: 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
11: 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 low side
- the aggregate of the high side and low side
- the high side
- 2.5 times the design pressure
12: The Board of Boilers adopts by reference
- Montreal Protocol Safety Code
- the MACS Pressure Vessel Code of Massachusetts
- the 1997 ANSI/ASHRAE Safety Code
- MSCA Code
13: A crankcase heater has a supplied voltage of 100 volts and is drawing 1.4 amps. What is the resistance?
- 80 ohms
- 27 ohms
- 104 ohms
- 71 ohms
14: No open flames are allowed in the machinery room unless?
- Approved by the installing contractor
- Approved by the authorized person
- Only when combustion air is provided from outside of the machinery room
- Never can be allowed
15: A 50 VA control transformer with a 25 volt control output would be rated for _________ amps.
- 1250
- 2.5
- 2
- There isn't enough information to answer.
16: Can you use Ammonia in industrial applications?
- No, never
- When mixed with R-718
- Yes, Under certain condidtions
- Yes, always
17: How does a centrifugal compressor create the pressure differential needed to move refrigerant through the system?
- Fan-like action
- Nesting scrolls
- Suction and discharge valves
- Rotating vanes
18: Ammonia vaporization takes place at what temperature?
- -32F
- -460F
- -110F
- -28F
19: On a single phase motor, when does the start winding cut out?
- 75% of its RLA speed
- 25% of its RLA speed
- 50% of its RLA speed
- 100% of its RLA speed
20: What is the refrigerant chlorodifluoromethane?
- R-22
- R-134a
- R-123
- R-12
21: When must refrigeration system covered by the code be inspected?
- Annually and when installed
- Upon installation
- Not required
- Annually
22: Ohm's Law indicates Amps X Resistance = ___________.
- Volts
- Current
- Ohms
- Impedance
23: When testing systems using non-positive displacement compressors, the entire system shall be considered for test purposes as the low side.
- True
- False
24: 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
25: Low ambient controls are used when
- economizers are used
- always
- when systems run all year round
- on air conditioning systems only