313A Evaporators and Condensers 2

Question 1

What is a flooded evaporator and where is it typically used?

Accepted Answer

An evaporator where the tubes are submerged in liquid refrigerant, used in large chillers to cool water flowing through the tubes

Answer

An evaporator with too much refrigerant — a fault condition

Answer

An evaporator damaged by water flooding

Answer

An evaporator with excessive frost buildup

Question 2

What is the split between sensible and latent cooling in an evaporator?

Accepted Answer

Sensible cooling changes temperature; latent cooling removes moisture — the ratio affects both comfort and coil selection

Answer

There is only sensible cooling in an evaporator

Answer

Sensible is for heating; latent is for cooling

Answer

The split only matters in commercial systems

Question 3

What is a direct expansion (DX) evaporator?

Accepted Answer

An evaporator where refrigerant expands directly inside the coil to cool air or fluid passing over or around it, with the metering device controlling flow

Answer

An evaporator that uses hot water for heating

Answer

An evaporator with no fins

Answer

An evaporator that uses a secondary coolant like glycol

Question 4

What is the purpose of a condenser fan cycling control?

Accepted Answer

To maintain adequate head pressure during low ambient temperatures by cycling condenser fans on and off

Answer

To reduce noise during nighttime operation

Answer

To increase airflow during peak cooling demand

Answer

To synchronize fan operation with the compressor

Question 5

How does a cooling tower work with a water-cooled condenser?

Accepted Answer

The cooling tower cools the condenser water through evaporation of a portion of the water, then returns the cooled water to the condenser

Answer

The cooling tower heats the water before it enters the condenser

Answer

The cooling tower stores water for emergency use

Answer

The cooling tower filters contaminants from the water

Question 6

What maintenance should be performed on evaporator coils?

Accepted Answer

Regular cleaning of fins and drain pan, checking drain lines, verifying airflow, and inspecting for corrosion or refrigerant leaks

Answer

Evaporator coils are maintenance-free

Answer

Only replace the entire coil when it stops working

Answer

Only the condenser requires regular maintenance