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A Short-Cycling AC Is Bad News: Here’s Why

spinning-fan-closeup“Short-cycling? What’s that?” We know it sounds like a strange circus act or a short-distance bicycling competition. But it’s a term for faulty behavior from a cooling system. If you hear your home’s AC starting and stopping multiple times over an hour, that’s short-cycling. This isn’t something you want to happen, since it spells trouble for your air conditioning in Burlington, VT. In most cases, you’ll need to call up HVAC technicians to find out why the AC is short-cycling and what to do about it.

Why is short-cycling a problem?

First, we must explain in greater detail what short-cycling means. When the thermostat of a house makes a request for cooling, the air conditioner starts up its fans and the compressor motor. The compressor is the component that allows for heat exchange and cooling of the air. The compressor remains running until the thermostat registers it has reached the target temperature, and then the compressor cycles down. In mild weather, the AC cycle lasts approximately 10 to 15 minutes and completes 2 to 3 times per hour.

If the compressor shuts down before completing its cycle, and then turns on again a short time later, it is  short-cycling. When you hear the compressor turn on and off every 10 minutes or less, something is wrong. The trouble could be within the air conditioner, ventilation system, or thermostat. The worst-case scenario is the air conditioner was installed poorly and is too large for the house, causing it to cool the space so rapidly that the thermostat prematurely registers the cycle is finished.

Why you don’t want short-cycling to happen

No matter the cause of short-cycling, you want it stopped for a number of reasons:

  • Large energy waste: An air conditioner consumes the most power during start-up. When caught in the start-up cycle, an air conditioner drains more electricity and will blast your utility bills into the stratosphere.
  • More repair needs: A compressor starting and stopping so often means extra wear on most parts of the AC. You can expect to call for repairs more often and spend more money keeping the air conditioner working.
  • Shortened system life: All the stress of an overworked compressor will condemn the air conditioner to an early retirement. What’s the most expensive repair an AC may need? Replacing it!
  • Uneven cooling: When the compressor shuts off before completing the cooling cycle, there’s not enough time to distribute cool air to all the rooms. A short-cycling AC won’t deliver the comfort you expect, leaving rooms too hot.

The Quick Short-Cycle Solution

Call for repair technicians! Yes, it’s that fast and easy. It takes experience HVAC technicians to diagnose short-cycling and find the root of the problem. Usually, the necessary repairs can be done rapidly to restore the AC. In the case of an oversized unit, however, the only remedy is replacing the entire system. (Yet another reason to only call on licensed HVAC professionals for AC installation. The pros take steps to ensure any new air conditioner is sized just right for the house.)

Repair your troubled air conditioner with a call to us! Red Rock Mechanical, LLC serves Northwest Vermont and Northeast New York.

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