Topics: All categories in the pool
1: The location of the thermal bulb for the TXV on the evaporator effects
- both the pressure and temperature in the feeler bulb
- the amount of superheat required to operate the TXV
- the amount of liquid in the evaporator
- the amount of gas in the evaporator
2: The critical temperature of a refrigerant gas occurs when
- any decrease in pressure will cause condensation
- any increase in pressure will not liquefy the gas
- the gas returns to a liquid
- the gas is no longer saturated
3: Class A refrigerants are considered
- non-flammable
- toxic
- non-toxic
- flammable
4: The main cause of enacting the "no vending rule" of July 1st 1992 was
- global warming potential
- ozone depletion
- both a & b
- None of the above
5: Materials used in construction and installation materials used in the manufacture or installation of refrigerating equipment shall be suitable for conveying refrigerant and the refrigerant oils and will not deteriorate in the presence of what?
- Moisture and air
- Air and dirt
- Oil and water
- Water and soap
6: Pressure vessels with an internal volume of 10 cubic feet or more
- shall use fusible plugs
- shall use pressure relief devices or fusible plugs
- shall use rupture discs or duel pressure relief valves
- shall use pressure relief devices
7: What is the purpose of a surge capacitor on a contactor?
- to protect low voltage equipment
- to keep the contactor pulled in
- to provide smoother start/stops
- to balance the sine waves
8: Can you use Ammonia in industrial applications?
- Yes, always
- When mixed with R-718
- Yes, Under certain condidtions
- No, never
9: By using nitrogen within a pipe during brazing operation,
- Copper oxide formation is prevented
- Exterior scale formation is minimized
- The explosion hazard is confined
- Discoloration is prevented
10: The Board of Boilers adopts by reference
- MSCA Code
- the MACS Pressure Vessel Code of Massachusetts
- the 1997 ANSI/ASHRAE Safety Code
- Montreal Protocol Safety Code
11: How is bring measured?
- hygrometer
- hydrometer
- manometer
- anemometer
12: The two basic types of evaporators are
- prime surface and finned
- direct expansion and plate
- finned and plate
- flooded and direct expansion
13: One atmosphere equals
- 29.4
- 0 psig
- 0 psia
- 14.7
14: How are safety controls wired in a circuit?
- Either series or parallel
- Series
- Series/parallel
- Parallel
15: The External equalizer of a TXV compensates for
- pressure within the evaporator
- pressure within the system
- pressure drop across the condenser coil
- pressure drop across the evaporator coil
16: "I" represents ____ in the Ohm's law formula.
- voltage.
- resistance
- capacitance
- amperage
17: R-12 is
- dichlorodifluoromethane
- trichlorofluoromethane
- dichloromethane
- dichlorofluoromethane
18: R-410A can segregate in the system or chemically change its composition due to a leak.
- True
- False
19: Setting a pressure relief device shall not exceed ___ of the design pressure
- 90%
- 80%
- 100%
- 75%
20: 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 the occupied 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 an unoccupied space
21: Which refrigerant replaced R-12?
- R-134A
- R-22
- R-410A
- R-407A
22: An accumulator can be located between the
- evaporator and compressor
- compressor and condenser
- first stage and second stage compressors
- condenser and evaporator
23: Evaporators within 18" of a heating coil must be equipped with a
- high limit control
- low limit control
- pressure relief device
- zone valve
24: What type of material can't be used on the outlet of a relief valve?
- Stainless steel
- PVC
- Magnesium alloy
- Copper
25: The difference between saturated liquid and saturated vapor is
- heat
- temperature
- pressure
- volume