Domestic refrigerators — which evaporator type is used most commonly? Identify the evaporator construction typically used in household (frost-free) refrigerators.

Introduction / Context:
Household refrigerators have evolved from manual-defrost (“frosting”) designs to frost-free configurations for user convenience, energy performance, and temperature uniformity. Understanding the prevalent evaporator type clarifies how automatic defrost and air circulation are implemented.

Given Data / Assumptions:

• Modern household (domestic) refrigerators, commonly “frost-free”.
• Forced air circulation across a finned evaporator with periodic defrost.
• Focus on mainstream residential appliances rather than special cases.

Concept / Approach:
A non-frosting (frost-free) refrigerator places a finned-tube evaporator in a separate air plenum. A fan circulates air over the coil and through the food compartments. An automatic defrost cycle removes accumulated frost without user intervention. This contrasts with older frosting evaporators (ice builds directly on the cold plate), which require manual defrost.

Step-by-Step Solution:
Identify goal of “frost-free”: avoid ice accumulation on user-accessible surfaces.Use hidden, finned evaporator with fan-forced air and heaters for timed/triggered defrost.Therefore, the common construction is the non-frosting evaporator.

Verification / Alternative check:
Product literature for residential refrigerators describes fan-cooled coils and automatic defrost (“auto defrost,” “no frost”), confirming the non-frosting design as standard.

Why Other Options Are Wrong:
(a) Frosting designs require manual defrost and are now uncommon in mainstream models. (c) “Defrosting evaporator” is not a standard category; all frost-free units have defrost but remain non-frosting in operation. (d) and (e) describe industrial or non-domestic hardware.

Common Pitfalls:
Equating any defrost-capable unit with “defrosting evaporator” rather than recognizing the standard non-frosting architecture.

Final Answer:
non-frosting evaporator