Service & TroubleshootingQuestion 80 of 110
Low airflow across an evaporator coil during cooling most commonly causes what?
a.High superheat at the coil
b.Higher supply air temperature
c.A cold, possibly frozen coil and low suction pressure
d.Higher condenser airflow
Explanation
Restricted evaporator airflow, from a dirty filter, blocked coil, or weak blower, reduces heat pickup so the coil runs colder and suction pressure drops, sometimes freezing the coil. Restoring airflow by cleaning filters and coils is the first corrective step. A frozen coil should be thawed before further diagnosis.
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