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Serving The Fresno & Madera Area


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Why Your AC Is Running Continuously


An air conditioning system that won’t turn on is obviously a major problem. But an air conditioning system that continues to run and run without cycling down is almost as big a problem. A nonstop air conditioner will waste massive amounts of energy, make parts of the house too cold, and wear down the unit rapidly so it needs multiple repairs and an early replacement.

What has turned your AC system into a runaway train? We’ll examine several potential causes below. You shouldn’t attempt to diagnose the problem on your own, however. You’ll need an expert HVAC contractor in Fresno, CA to figure out what’s wrong and how best to fix it.

The AC is too small for the house

If this is a new air conditioning system going through its first summer, nonstop operation is often warning that whoever installed it failed to correctly size it to match the house. Sizing a new air conditioning system is an essential part of installation, but many amateurs skip this part and guess—leading to the home having a cooling system that’s not powerful enough. The AC will continue to run because it can’t reach the temperature the house requires for comfort. The only repair for this is a full air conditioning replacement.

The thermostat has a lost connection

A common cause for an air conditioner stuck in its cooling cycle is a thermostat that has lost its connection to the AC. A standard thermostat has separate wires to signal the fan and compressor to turn on and turn off. If the thermostat loses the connection that sends the “off” signal, then no matter how you set the thermostat the air conditioner will continue to run. Technicians can repair or replace the thermostat to stop this.

The air conditioner has lost refrigerant

Refrigerant leaks create major problems in an air conditioner, eventually leading to a full breakdown. Continuous operation is one warning sign of low refrigerant: the reduced amount of refrigerant makes it harder for the AC to cool the house and forces it to work nonstop. Refrigerant leaks need immediate professional attention. Technicians must seal the leaks and then restore the lost amount of refrigerant.

The evaporator coil has frozen

You should never see ice on your air conditioner. Ice can start to develop along the evaporator coil because of a clogged air filter, refrigerant leaks, or dust and dirt along the coil’s surface. Whatever the source of the ice, it will prevent the coil from absorbing heat and this will force the AC to run constantly. Don’t attempt to “fix” this by scraping off the ice. It won’t address the underlying problem and you may damage the coil. Let professionals handle this.

Dirt on the condenser coil

The outside coil of an air conditioning system is responsible for releasing heat to the outdoors. If this coil has gotten excessively dirty, it will trap heat inside the AC and restrict its ability to cool, leading to the continuous operation. Let professionals clean the coil so it won’t become damaged.

Rely on Purl’s Sheet Metal & Air Conditioning for your AC service in the Central Valley. “Quality Is the Cornerstone of Our Success” since 1952.

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