Broan Central air conditioner won't turn off

Won’t your Broan air conditioner turn off? The system may be receiving a continuous run signal even after the thermostat is set to Off. a shorted contactor or a bad wall thermostat or thermostat wiring is the most likely cause, keeping a cooling signal on the yellow (Y) terminal even after the thermostat is set to Off. A shorted furnace control board or main control board can cause the same problem, though it is a less common cause, by continuing to send voltage to the outdoor condensing unit and making the air conditioner run constantly. Either board can send uninterrupted voltage to the central air condensing unit, causing the central air to keep running. A stuck wall thermostat or thermostat wiring is another common cause. Its electrical contacts may remain closed between the common "C" and yellow "Y" thermostat wire terminals, continuing to energize the contactor. If those parts test properly, a shorted contactor may be keeping the outdoor unit running. This can result in an air conditioner running constantly, an AC that won't shut off, or central air that won't turn off. Turn off power before inspecting components, and have a licensed HVAC technician handle testing or replacement involving 240V line voltage. Thermostat testing and replacement may be within DIY scope if performed safely. Enter your Broan model number to find the exact replacement control board, thermostat, or contactor for your central air conditioner.

01 - Broan Central Air Conditioner Control Board

If the furnace control board has a short, it may be providing continuous voltage to the central air condensing unit preventing it from turning off. Inspect the control board for any damage and replace if necessary.

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Common

02 - Broan Central Air Conditioner Main Control Board

If the furnace's main control board has a short, it may be providing continuous voltage to the central air condensing unit preventing it from turning off. Inspect the control board for any damage and replace if necessary.

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Common

03 - Broan Central Air Conditioner Wall Thermostat

The wall thermostat has electrical contacts that send signal voltage back to the control board and the condensing unit's contactor to run the central air system. If the contact that controls the contactor sticks closed, it will send continuous voltage to the contactor, causing the central air system to run continuously. To determine if the thermostat is defective, use a multi-meter to test it for continuity. If the wall thermostat shows continuity between the common (“C”) and yellow (“Y”) thermostat wire terminals when the thermostat is in the off position, the thermostat has failed and will need to be replaced.

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Common

04 - Broan Central Air Conditioner Wifi Thermostat

The WiFi thermostat has electrical contacts that send signal voltage back to the control board and the condensing unit's contactor to run the central air system. If the contact that controls the contactor sticks closed, it will send continuous voltage to the contactor, causing the central air system to run continuously. To determine if the thermostat is defective, use a multi-meter to test it for continuity. If the WiFi thermostat shows continuity between the common (“C”) and yellow (“Y”) thermostat wire terminals when the thermostat is in the off position, the thermostat has failed and will need to be replaced.

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Common

05 - Broan Central Air Conditioner Contactor

The furnace control board sends a low voltage signal to the contactor. When the contactor receives the signal from the control board, it closes the circuit, sending voltage to the condensing unit components. If the contactor has shorted, it can send continuous voltage to the condensing unit's components resulting in the central air system not turning off. To determine if the contactor is at fault, use a multimeter to test the contactor for a short. If the contactor has shorted, replace it.

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Less Common

Frequently Asked Questions

Why won't my Broan central air conditioner turn off?

How can I tell if the thermostat is causing my AC to keep running?

Can a bad AC contactor make the central air conditioner run continuously?

How do I know whether the Broan control board is bad when my AC won't shut off?

How do I find the correct Broan AC thermostat, contactor, or control board replacement part?

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