Massachusetts Refrigeration Tech/Contractors practice quiz
Refrigeration RT/RC Prep Quiz
Topics: All categories in the pool
1: pressure relief valves must discharge to the atmosphere at a location not less than 15 feet from ground level and ____ feet from any window, ventilation opening, or exits of buildings.
20
10
15
25
2: A relief valve shall be located at least ___ above grade.
25'
10'
15'
36'
3: High side floats are used on centrifugal chiller systems are are considered critically charged systems.
are obsolete.
True
False
depends on the type of refrigerant being used
4: The pressure relief device of a positive displacement compressor shall discharge in the ______________or in accordance with 9.7.8
low side of the system
the liquid side of the system
high side of the system
the vapor side of the system
5: Capacitors are rated in
volt - amperes
micro-farads
megaohms
kelvins
6: Which is the lowest vacuum?
1,000 Microns
5 psig
10 psia
5" hg
7: What pipe can not be used for refrigeration?
L
K
M
N
8: On a pumpdown system, the liquid-line solenoid is controlled by the
defrost timer
thermostat
low pressure switch
low-ambient controller
9: On a large centrifugal system, what meters the flow to the evaporator?
TXV
Low side float
High side float
Cap tube.
10: Where must a refrigeration contractor's license number be displayed?
Uniforms, checks, and invoices.
Truck, office, every job, and on all equipment
Trucks, invoices, and advertising
Trucks, license plates, and uniforms
11: Ohm's Law indicates Amps X Resistance = ___________.
Volts
Ohms
Current
Impedance
12: The actual expansion curve of compression follows most nearly which one of the following curves?
Adiabatic
Volume Temperature
Pressure Temperature
Isothermal
13: 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
14: Which refrigerant was still able to be vented to the atmosphere after July 1, 1992?
R-22
R-11
R-12
R-113
15: A high side float is a
float type valve that controls the crankcase oil level
metering device used on critically charged systems that controls the level of the liquid refrigerant in the high pressure side of the system.
float type switch that stops the compressor when the pressure on the high side becomes too high
float type valve that controls the amount of refrigerant stored in the receiver
16: "R" represents ___ in the Ohm's law formula
voltage
capacitance
resistance
amperage
17: According to ASHRAE Standard-15 9.8 Positive Displacement Compressor Protection, the pressure-relief device discharge into
the low-pressure side of the system
the high side of the system
the liquid receiver
both a and c are correct
18: How does a centrifugal compressor create the pressure differential needed to move refrigerant through the system?
Fan-like action
Suction and discharge valves
Nesting scrolls
Rotating vanes
19: It takes how many BTU/hr to melt one pound of ice at 32F
180
970
144
212
20: Pressure vessels shall be provided with ___________in accordance with Section VIII of the ASME Boiler & Pressure Vessel Code
over pressure protection
Pressure vessels need no type of protection as long as it is hydrostatically tested every three months
over pressure protection and a rupture disc
over pressure protection as well as a temperature protection device
21: A line voltage thermostat controls a 1,200 watt strip header at 120 volts. What must be minimum ampere rated of the stat be?
10 amps
20 amps
5 amps
15 amps
22: A R-22 system running with a condensing temperature of 110F and a 40F evaporator temperature will read pressures of ____ on the high side and ____ on the low side.
257 psig, 77 psig
226 psig, 68 psig
350 psig, 120 psig
455 psig, 185 psig
23: The solution that is pumped into the concentrator in an absorption chiller is referred to as the
concentrated solution
weak solution
strong solution
absorbed solution
24: What must be done if refrigeration lines pass through a concrete floor?
insulated
installed through a pipe casing
moisture barrier
leak checked
25: If the spring is adjusted to increase the superheat, this new setting will