HVAC Refrigeration 3

Question 1

What does a high-pressure cutout switch do in a refrigeration system?

Accepted Answer

Stops the compressor when discharge pressure exceeds a safe limit

Answer

A high-pressure cutout switch shuts off the compressor when discharge pressure exceeds a preset limit to prevent equipment damage.

Question 2

What is the primary purpose of an accumulator in a refrigeration system?

Accepted Answer

Prevent liquid refrigerant from entering the compressor

Answer

An accumulator is installed in the suction line to catch any liquid refrigerant before it reaches the compressor, preventing compressor damage from liquid slugging.

Question 3

What is the Global Warming Potential (GWP) used to measure?

Accepted Answer

The heat-trapping ability of a refrigerant relative to CO2 over 100 years

Answer

GWP measures how much heat a greenhouse gas traps compared to CO2 over a 100-year period, with CO2 having a GWP of 1.

Question 4

In a refrigeration system, 'head pressure' refers to which pressure?

Accepted Answer

Discharge pressure at the compressor outlet

Answer

Head pressure is the high-side discharge pressure measured at the compressor outlet, representing the condensing pressure of the refrigerant.

Question 5

What refrigerant safety classification is assigned to ammonia (R-717)?

Accepted Answer

B2L (toxic, low flammability)

Answer

Ammonia is classified B2L — toxic (B) and mildly flammable (2L) — making it effective for industrial refrigeration but requiring special safety precautions.

HVAC Practice Test

HVAC Practice Test

HVAC Refrigeration 3