Topics: All categories in the pool
1: A water regulating valve opens when
- when the power is on
- when the power is on there is an overcharge of refrigerant
- the head pressure rises
- the compressor is on
2: When must refrigeration system covered by the code be inspected?
- Not required
- Annually
- Annually and when installed
- Upon installation
3: On a ammonia compressor, the pressure of a forced fed oil pump is changed by varying the
- opening at the pump inlet
- opening at the pump outlet
- cooling temperature set-point
- adjustment of the spring tension of the TXV
4: A halide torch is most useful with a freon compression system
- to release a sticking valve
- to detect refrigeration leaks in piping joints
- to remove from from TXV's and evaporator coils
- to sweat flanges on the refrigeration piping
5: A High-Probability System
- is such that a leak of refrigerant from a failed connection will enter an unoccupied space
- is such that a leak of refrigerant from a failed connection will enter the occupied space
- is a system highly likely to leak form a failed connection or component of such system
- is such that any leak will cause injury or death to anyone within a 100 square foot area
6: What type of oil is used in R-410A systems?
- mineral oil
- polyalkylene glycol (PAG)
- naphthene
- polyolester (POE)
7: A hissing noise at the expansion valve is a good indication that
- gas is passing thru it
- nothing is passing thru
- expansion valve is oversized
- liquid is passing thru it
8: Most CFC's are
- inert but toxic
- toxic
- inert
- flammable
9: If the power element of an expansion valve should lose its charge the valve would
- go open
- overfeed the evaporator
- underfeed the evaporator
- go closed
10: Cooling tower lowers condenser water temp by
- running water thru a secondary heat exchanger
- evaporative cooling
- condensation
- running fans at 100%
11: A 120 volt motor rated at 1,800 watts. You find the motor is drawings 25 amps. The motor is
- drawing RLA and is running as it should
- drawing LRA and is seized and should be replaced.
- running hot
- none of the above
12: When can 50/50 solder be used?
- in the low side
- in the high side
- liquid and suction lines
- none of the above.
13: It takes how many BTU's of latent heat/hr to boil 1 lbs of water into steam?
- 970 BTU
- 24,000 BTU
- 144 BTU
- 12,000 BTU
14: Which of the following most closely represents the concentration of Li-Br in a absorption system?
- 50% Li-Br, 50% tap water
- 60% Li-Br, 40% distilled water
- 40% Li-Br, 60% tap water
- 40% Li-Br, 60% distilled water
15: Adjusting the spring pressure on a TXV
- changes superheat
- changes subcooling
- adjusts the bulb charge
- makes no difference
16: Which of the following is an inorganic refrigerant?
- R-22
- Ammonia
- Chlorofluorocarbons
- All of the above
17: Defined process piping by code CMR (528)
- Any piping that conveys a solid, liquid or gas that is not part of the plumbing or fire protection system
- Any piping in an industrial space
- Any piping in an industrial or commercial space
- All of the above
18: Ammonia vaporization takes place at what temperature?
- -460F
- -110F
- -32F
- -28F
19: The first step in mechanical refrigeration is
- expansion
- condensation
- compression
- evaporation
20: Suction line oil traps should be installed when the condenser is
- in the basement and the evaporator is on the third floor
- more than 100' away from the evaporator
- located outside the operates in temperatures below 35F
- on the third floor roof and the evaporator is in the basement
21: Pressure is equivalent of
- Area X Force
- Force / Area
- Force X Area
- Force
22: Transformers are rated in
- volts
- volts-ohms
- volt-amps
- amps
23: If a low-pressure chiller has a low-side leak, which of the following will most likely result?
- High suction pressure and high discharge pressure.
- Low suction pressure and low discharge pressure
- High head pressure and low suction pressure
- Low head pressure and high suction pressure
24: What is the typical air conditioning operating pressures for 410A?
- 60 psi suction, 210 psi discharge
- 25 psi suction, 125 psi discharge
- 105 psi suction, 350 psi discharge
- None of the above
25: A class A3 refrigerant is considered
- toxic and somewhat flammable
- toxic and non-flammable
- non-toxic and non-flammable
- non-toxic but highly flammable