Fundamentals of Air Conditioning Systems Flashcards

What is the primary purpose of a metering device in a refrigeration circuit?

Answer: To reduce refrigerant pressure and control flow into the evaporator

The metering device drops refrigerant pressure and regulates flow into the evaporator, enabling it to absorb heat effectively.

Which refrigerant cycle process occurs in the condenser?

Answer: Condensation and heat rejection to outdoor air

In the condenser, high-pressure refrigerant vapor releases heat to the outside air and condenses into a liquid.

What does superheat measure in an air conditioning system?

Answer: Temperature rise of refrigerant vapor above its saturation temperature

Superheat is the number of degrees the refrigerant vapor has risen above its boiling point at a given pressure.

A residential split system has the evaporator coil located in the:

Answer: Indoor air handler or furnace plenum

In a split system, the evaporator coil is installed indoors in the air handler or above the furnace to cool circulating air.

What is subcooling in a refrigeration system?

Answer: Chilling the refrigerant liquid below its condensing saturation temperature

Subcooling is the number of degrees the liquid refrigerant is cooled below its saturation condensing temperature, improving system efficiency.

In a vapor-compression cycle, which component raises refrigerant pressure and temperature?

Answer: Compressor

The compressor draws in low-pressure vapor and raises it to high pressure and temperature before sending it to the condenser.

What effect does a dirty evaporator coil have on system performance?

Answer: Reduces airflow and causes low suction pressure and possible coil freezing

A dirty evaporator restricts airflow, which lowers heat absorption, reduces suction pressure, and can cause ice formation on the coil.