ESCO Air Conditioning Practice Exam 2026 - Free AC Certification Practice Questions and Study Guide

Short cycling in an air conditioning unit occurs when the system frequently turns on and off in rapid succession, failing to complete a full cooling cycle. This issue is commonly attributed to oversized units. When an AC unit is too large for the space it is conditioned, it cools the area quickly and reaches the thermostat setting almost immediately. As a result, the thermostat signals the unit to shut off before adequate dehumidification has taken place, which can lead to discomfort and may cause the system to short cycle repeatedly.

When examining other factors that might contribute to short cycling, such as faulty thermostats, inadequate insulation, or dirty filters, these issues typically affect the efficiency and operation of the system but do not directly cause it to short cycle in the same manner as having an oversized unit. Faulty thermostats can lead to improper temperature readings, which may result in running or shutting off at incorrect times, but they do not inherently cause the system to cycle short if properly functioning. Inadequate insulation can lead to energy loss and thermal discomfort but doesn't contribute to the rapid cycling issue. Similarly, dirty filters can restrict airflow and cause the system to overheat and shut down as a protective measure, but the primary, immediate cause of short cycling is more directly linked to