Topics: All categories in the pool
1: What is specific heat?
- measured heat
- heat required to raise the temperature of 1lb of a substance 1 degree
- the specific heat required to change the state of one cubic foot of air to steam
- none of the above
2: What type of refrigerants are NOT flammable?
- CHC
- HFC
- HCFC
- All of the above
3: Pressure is equivalent of
- Force / Area
- Force
- Force X Area
- Area X Force
4: All serviceable components of a refrigeration system shall be provided with
- name plates with markings referring to pressure and temperature in accordance with ASME Boiler and Pressure Vessel Code
- manufactures instructions on start-up procedures
- service manuals
- safe access
5: _____ alloys shall not be used in contact with an halogenated refrigerants.
- Nickel
- Copper
- Zinc
- Magnesium
6: Halogenated refrigerants cannot be used with what material?
- Magnesium alloy
- Aluminum
- Copper
- Stainless steel
7: One atmosphere equals
- 0 psig
- 29.4
- 0 psia
- 14.7
8: System design pressures must take into consideration, not only, pressures found during normal operation but also what?
- When it's cold out
- When there is a malfunction on the high side
- When its warm out
- All of the above
9: What is the purpose of a surge capacitor on a contactor?
- to protect low voltage equipment
- to provide smoother start/stops
- to keep the contactor pulled in
- to balance the sine waves
10: Where are the three places that the discharge from an ammonia relief valve be piped?
- To chemical neutralizing tank only
- Underground, into drain, into mechanical room
- Atmosphere, Tank containing water, where the AHJ indicates.
- None of the above.
11: A single pole-double throw switch used how many wires excluding the ground wire?
- two
- four
- five
- three
12: If a liquid receiver is designed to receive the refrigerant charge during a pumpdown procedure, it shall have the capacity to
- release the charge when the pressure exceeds 310 psig or higher
- Pumpdown procedures are not allowed with systems containing liquid recievers
- receive the pumpdown charge
- hold up to 110% of the pumpdown charge
13: When air is ducted through a machine room that services occupied space, What must be done?
- Welded and seamed.
- Insulated and cross broke
- Flanged and gasketed
- Ducted and sealed
14: How many closing forces operate a thermostatic expansion valve?
- 1
- 2
- 4
- 3
15: A normally operating R-410A system with a condensing temperature of 110F will have a high side pressure of around ______ psig
- 365 psig
- 125 psig
- 255 psig
- 327 psig
16: An azeotropic refrigerant is
- a mixture of two or more refrigerants that boil at about the same temperature minimizing temperature glide.
- a mixture of two or more refrigerants that boil at much different temperatures causing temperature glide
- a mixture of two or more refrigerants that boil at much different temperatures minimizing temperature glide
- none of the above
17: The absorber shell contains the
- condenser and the generator
- condenser, the evaporator, and the generator
- condenser and the absorber
- evaporator and the absorber
18: When should a relief valve start to function?
- Before the purge station discharges
- 10 psi before it's set pressure
- Two times it's working pressure
- At it's set pressure
19: Refrigerant systems containing Group I refrigerants can be installed in or on public stairways.
- True
- False
20: A secondary coolant is defined as
- any refrigerant direcly in contact with the cooling space for process cooling
- a low temperature refrigerant used for cascading systems
- a combination of interconnected parts from a closed circuit in where fluid is circulated for the purpose of cooling for a refrigeration system.
- any liquid used for the transmission of heat without a change of state in A/C refrigeration systems having flash point above 150F
21: All welding done on any refrigeration system or piping covered by 522 CMR 9.00 shall be performed by a according to Section IX of the ASME code
- licensed welder
- licensed technician
- competent welder
- welder qualified
22: Adjusting the spring pressure on a TXV
- changes subcooling
- adjusts the bulb charge
- changes superheat
- makes no difference
23: A person holding a license as a refrigeration technician may connect or disconnect for the purpose of installation, repair, or replacement, any electrical device or control to be a part of a refrigeration or air conditioning system, from the
- 24 volt secondary side of the Class 2 transformer to the thermostat
- load-side of the contactor in
- first disconnect in
- breaker panel in
24: On a single phase motor, when does the start winding cut out?
- At 50% of its full rated speed
- At 25% of its full rated speed
- Start windings do no cut-out of the run cycle
- At 75% of its full rated speed
25: Name an HCFC refrigerant(s):
- R-22
- R-123
- R-11
- both a & b