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Heating & Heat Pumps

What is Short-Cycling?

Short-cycling is when an air conditioner, heat pump, or furnace turns on and off in rapid, brief cycles instead of running full cycles. Common causes include oversized equipment, a poorly located thermostat, clogged filters, low refrigerant, and overheating or safety controls tripping. It wastes energy, wears out components faster, and leaves temperatures uneven.

Why it matters to you

In a Charleston summer, a short-cycling AC shuts off before it removes much moisture, so the house can hit the thermostat setting and still feel damp. It is one of the most common reasons for a cool-but-clammy home.

Practical guidance

Start with the easy checks: replace a dirty filter and make sure the thermostat is not near a supply vent, sunny window, or kitchen. If cycles stay short, have a licensed technician check refrigerant charge, safety controls, and whether the system is oversized for the home.

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