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HomeRepair HelpTempstar Central A/C RepairTempstar Central air conditioner wall thermostat not working properly Repair
Tempstar Central air conditioner wall thermostat not working properly
When a Tempstar central air conditioner thermostat is not working, the wall thermostat is the most likely cause. A failed thermostat may have a blank display, receive power but fail to send a cooling signal, or stop communicating with the air handler and outdoor unit. A wall thermostat can show the same symptoms. If the thermostat display is blank, check and replace its batteries when applicable, then inspect the Tempstar control board, which supplies 24-volt power and regulates thermostat operation. Less common causes include an incoming power problem, such as a tripped circuit breaker, blown fuse, or turned-off service switch, and damaged thermostat wiring. These checks can help diagnose an ac thermostat not working, central air thermostat not working, or thermostat not turning on the AC. Turn off power before removing wiring, and use caution around the furnace or air handler because incoming power and some circuit components carry line voltage. Testing or repairing line-voltage circuits is best left to a qualified technician. Enter your Tempstar central air conditioner model number to find the exact replacement thermostat, wall thermostat, control board, transformer, fuse, or thermostat wire for your specific system.
01 - Tempstar Central Air Conditioner Wall Thermostat
The wall thermostat is responsible for controlling components and regulating the home's temperature. The thermostat can be powered with 24 volts from a control board on a separate unit like a furnace or air handler, or from batteries in the thermostat itself. The thermostat also has terminals to receive and distribute low voltage 24 volt power to run different HVAC products such as a furnace, air conditioner, or heat pump. If the wall thermostat is receiving power but the display is dead, or it will not send power out in the appropriate modes, the wall thermostat will need to be replaced.
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Highly Likely
02 - Tempstar Central Air Conditioner Wifi Thermostat
The WiFi thermostat is responsible for controlling components and regulating the home's temperature. The thermostat is usually powered with 24 volts from a control board on a separate unit like a furnace or air handler. The thermostat also has terminals to receive and distribute low voltage 24 volt power to run different HVAC products such as a furnace, air conditioner, or heat pump. If the WiFi thermostat is receiving power but the display is dead, or it will not send power out in the appropriate modes, the WiFi thermostat will need to be replaced.
Highly Likely
03 - Wall Thermostat Batteries
Most wall thermostats are either powered by an enclosed battery or by the furnace or air handler control board. If the thermostat display is dead, you can remove the thermostat cover and look for replaceable batteries. Replace the batteries if needed and check operation.
Common
04 - Tempstar Central Air Conditioner Control Board
The control board regulates the power supply to all of the components in the system. If the control board fails, it might not send voltage to the thermostat, leaving the thermostat inoperable.
Less Common
05 - Incoming Power Problem
Check to see if there is power to the furnace or air handler. One or more indicator lights on the control board should be illuminated. If there is no power to the furnace or air handler, check to see if a circuit breaker has tripped or a fuse has blown. Confirm the power switch on the side of the unit is turned on.
Less Common
06 - Bad Wall Thermostat Wiring
In order to send signals from and to the indoor and/or outdoor units, the wall thermostat uses a group of wires usually called thermostat wiring. If the thermostat wiring gets damaged, certain functions of the system or the thermostat itself may not function properly. The thermostat wiring can be checked for power or continuity with a multimeter. The wiring is usually industry standard colors: Red/White/Yellow/Green for a four-wire system.
Less Common
Frequently Asked Questions
Why is my Tempstar central air conditioner thermostat not working?
Why is my thermostat not turning on the AC?
How can I tell whether the thermostat, transformer, or control board is bad?
How do I replace a Tempstar wall or wall thermostat?
How do I find the correct Tempstar thermostat replacement part?
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