TESTED QUESTIONS AND PRACTICE
SOLUTION GRADED A+
◉ What does RSES stand for?
Answer: Refrigeration Service Engineers Society
◉ What does ACCA stand for?
Answer: Air Conditioning Contractors of America
◉ What does AHRI stand for?
Answer: Air-Conditioning, Heating & Refrigeration Institute
◉ What does ASHRAE stand for?
Answer: American Society of Heating, Refrigerating and Air-
Conditioning Engineers
◉ What does NATE stand for?
Answer: North American Technical Excellence
◉ What section of the EPA regulations requires technician
certification?
,Answer: EPA section 608
◉ List the different types of cooling mechanisms.
Answer: Evaporative, thermoelectric, absorption, mechanical
compression
◉ Which type of cooling mechanism is used in the most
applications?
Answer: Compression cycle
◉ Briefly explain the fundamental principles that make the
compression refrigeration cycle work.
Answer: "Cold" is not a substance or an energy form, it is the lack of
heat.Heat travels from hot to cold.Liquids absorb large amounts of
heat when they boil off to a gas. Gasses give off large amounts of heat
when they condense to a liquid. When something is boiling or
condensing its temperature remains the same.The temperature at
which a liquid boils is controlled by its pressure.
◉ What does an air conditioner do with the heat in your house?
Answer: It moves the heat from inside the house to outside the
house.
,◉ How does a compression cycle refrigeration system move heat
from a relatively cold temperature to a relatively warm temperature?
Answer: It boils refrigerant at a low pressure and temperature to
absorb heat inside and condenses refrigerant at a high temperature
and pressure to release heat outside
◉ Explain why boiling is considered a cooling process.
Answer: Boiling requires heat. When a liquid boils it extracts heat
from whatever it is touching.
◉ List the four major components of the compression refrigeration
cycle in order
Answer: Compressor, condenser, metering device, evaporator
◉ Why do both the compression cycle and absorption cycle have a
high pressure side and a low pressure side?
Answer: The low pressure side allows refrigerant to boil at a
temperature below the temperature of the space being cooled,
absorbing heat. The high side pressure allows the refrigerant to
condense at a temperature higher than the outdoor temperature,
releasing heat.
◉ What components are responsible for maintaining the high and
low pressures in a compression refrigeration system?
Answer: The compressor and the metering device.
, ◉ What are the three refrigerant conditions inside a compression
cycle system?
Answer: Saturated, Superheated, and subcooled
◉ What components are responsible for maintaining the high and
low pressures in an absorption refrigeration system?
Answer: The generator, the absorber, and the solution pump
◉ What are the two cycles that make an absorption system work?
Answer: The refrigeration cycle and the solution cycle
◉ Explain how an evaporative cooling system works.
Answer: Water flows over media and air is pulled across the wetted
media. Some of the water evaporates, cooling off the air.
◉ Where is evaporative cooling the most effective?
Answer: Dry climates, like the southwestern United States.
◉ What is the advantage of the Maisotsenko Cycle?
Answer: The Maisotsenko Cycle can reduce the air temperature
more than standard evaporative coolers and is effective in areas that
traditional evaporative coolers are not.