Refrigeration Fundamentals & System Components Flashcards

What is the primary function of a thermostatic expansion valve (TXV) in a refrigeration system?

Answer: Meter refrigerant flow to maintain superheat at the evaporator outlet

A TXV meters refrigerant flow into the evaporator to maintain a set superheat, preventing liquid slugging at the compressor.

Which refrigerant property is measured by a gauge manifold's high-side gauge during normal operation?

Answer: Condenser saturation pressure

The high-side gauge reads the discharge pressure, which corresponds to the condenser saturation pressure.

Subcooling in a refrigeration system refers to cooling the liquid refrigerant:

Answer: Below its condensing temperature

Subcooling lowers liquid refrigerant temperature below its saturation point, preventing flash gas before the expansion device.

A filter-drier in a refrigeration system is primarily installed to:

Answer: Remove moisture and contaminants from the refrigerant

Filter-driers adsorb moisture and trap particulates to protect the expansion device and compressor from damage.

The suction line accumulator is designed to protect the compressor from:

Answer: Liquid refrigerant slugging

An accumulator collects liquid refrigerant and oil before the compressor inlet, releasing only vapor to prevent hydraulic damage.

On a pressure-enthalpy (P-H) diagram, the horizontal distance across the evaporator represents:

Answer: Latent heat absorbed (refrigerating effect)

The evaporator process appears as a horizontal line at low pressure; its horizontal length equals the enthalpy change, which is the refrigerating effect.

Which type of condenser uses ambient air blown across the coil by a fan to reject heat?

Answer: Air-cooled condenser

Air-cooled condensers use fans to move ambient air over finned coils, transferring refrigerant heat directly to the air.