Massachusetts Refrigeration Tech/Contractors practice quiz
Refrigeration RT/RC Prep Quiz
Topics: All categories in the pool
1: Refrigerant restricted in 2004 but used for transition for decades:
R-22
R-123
R-134A
R-11
2: Name three things that must be done when changing refrigeration lubricant?
Make sure it's compatible, notify owner, notify AHJ
You can't change lubricants.
Place sign, check for leaks, insulate
Nothing must be done
3: What is the minimum height refrigeration piping should be placed against walls?
Ceiling height
72"
7.25'
6'
4: The reversing valve is commonly used
on all heat pumps
on commercial system that involve two different temperatures
when the code requires a check valve
on multiple compressor systems
5: How many gallons of water per pound of ammonia do you need?
20
1
5
15
6: When releasing a hydrogenated hydrocarbon refrigerant to the atmosphere, ample ventilation must be provided and
gas masks must be worn
explosion precautions must be taken
the owner shall be informed
no flames shall be permitted
7: The amount of heat required to raise the temperature of 1 lb of water 1F is?
1 BTU
1 Kelvin
The rate of conduction
1 Therm
8: A water regulating valve opens when
when the power is on there is an overcharge of refrigerant
the head pressure rises
when the power is on
the compressor is on
9: Which of the following is a drop-in for R-22
R-410A
R-134A
R407C
None of the above
10: How many volts would you read on a 480V system phase to phase?
0
277
480
1/3 the voltage
11: The critical temperature of a refrigerant gas occurs when
any decrease in pressure will cause condensation
the gas returns to a liquid
the gas is no longer saturated
any increase in pressure will not liquefy the gas
12: How would you know if there was a loss of crankcase pressure?
oil will thin out
oil will thicken
oil will foam
oil level will rise
13: Heat is a form of
power
matter
work
energy
14: What is the minimum size of the discharge pipe?
Same size as the outlet of the relief valve
One pipe size larger that the inlet of the relief valve
Depends on size of manifold
All of the above
15: What are the three components of a transformer?
Contacts, secondary coil, and core
Primary coil, secondary coil, and copper contacts
Primary core, secondary coil, and high and low voltage connectors.
Primary coil, secondary coil, and core
16: Liquid level gauge glasses shall have automatic closing shut off valves, except Bull's eye or reflex type.
True
False
17: How much clearance do you need around the perimeter of electrical panels?
12"
36"
18"
24"
18: How many flammability classifications are refrigerants in?
3
7
5
2
19: 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
20: Low temperature systems should have what?
High pour point
Low pour point
High viscosity
None of the above
21: Doors communicating with outside from a mechanical room must be?
Self-closing, aligned, fire door
Steel, approved, weather-stripped
Self-closing, approved, fire door
Self-closing, wooden, fire door
22: The formula for Pure Power in a resistance circuit is
Kw = volts X amps
Watts X amps.
Watts X power factor
Watts = volts X amps
23: All serviceable components of a refrigeration system shall be provided with
manufactures instructions on start-up procedures
service manuals
name plates with markings referring to pressure and temperature in accordance with ASME Boiler and Pressure Vessel Code
safe access
24: When a receiver is greater than 3 cubic feet but less than 10 cubic feed, what is the minimum relief device required?
fusible plug
relief valve
rupture disc
all of the above
25: How many refrigerant classifications are there for toxicity?