After a system cleanup, which evaporator value should be measured?

After a system cleanup, which evaporator value should be measured?

• A. Entering air dry bulb temperature
• B. Entering air wet bulb temperature
• C. Saturation temperature of refrigerant
• D. Evaporator pressure

Answer: (B)

The key parameter for evaluating evaporator performance is the entering air wet-bulb temperature. Why this matters: the evaporator removes both sensible heat (cooling the air) and latent heat (removing moisture). The amount of moisture the coil must remove depends on how humid the incoming air is, which is captured by the wet-bulb temperature. Wet-bulb combines temperature and humidity into a single indicator of the air’s moisture content, making it the most informative measure for assessing how effectively the evaporator is dehumidifying and cooling the air after a system cleanup. In contrast, dry-bulb only reflects sensible cooling and misses humidity effects, while saturation temperature of the refrigerant or evaporator pressure reflect refrigerant-side conditions rather than the air-side performance.

The key parameter for evaluating evaporator performance is the entering air wet-bulb temperature. Why this matters: the evaporator removes both sensible heat (cooling the air) and latent heat (removing moisture). The amount of moisture the coil must remove depends on how humid the incoming air is, which is captured by the wet-bulb temperature. Wet-bulb combines temperature and humidity into a single indicator of the air’s moisture content, making it the most informative measure for assessing how effectively the evaporator is dehumidifying and cooling the air after a system cleanup. In contrast, dry-bulb only reflects sensible cooling and misses humidity effects, while saturation temperature of the refrigerant or evaporator pressure reflect refrigerant-side conditions rather than the air-side performance.