10K 3380 600mm Micro Temperature Sensor , High Temperature Thermocouple Probe

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Air Conditioner Temperature Thermostat Sensor Problems

There are times when your air conditioning unit seems to be on the fritz and at the worst possible times. When this happens, it could be due to a sensor problem. Troubleshooting this problem can be rather easy if you know what to look for. However it is easier to know what to look for if you know exactly how sensors work. Air Supply Heating & Air Conditioning will share how a thermostat sensor works and what symptoms to look for when troubleshooting a faulty sensor. By determining your air conditioner problem, you can stay cool for the rest of the summer.

How Does a Thermostat Sensor Work in an Air Conditioner?

The thermostat sensor is located near the evaporator coils. These coils are inside your air conditioner unit. As the air is sucked through the return vents, the air passes by the sensor and the coils. As the air passes the sensor, it reads the temperature and compares that reading to the setting on your thermostat. If the air is warmer then your desired setting, the sensor will activate the compressor or in other words, begin to cool the inside of the building. It also works in reverse if the air passing the sensor is lower, or at the same temperature set on your thermostat. If this happens, it will shut off the compressor. This is the main function of the thermostat sensor.

Symptoms of a Bad Thermostat Sensor

When the sensor isn’t working correctly, it may cycle on and off randomly between proper activation periods. This means if your home is too hot or too cold, the thermostat may switch on or off before the proper temperature is met or when the inside can be too cold or warm inside. The main indicator of a failing or faulty sensor is erratic cycles.

DIY Thermostat Sensor Repairs

There are some simple repairs you can try first before calling out an HVAC technician. Start by turning off the air conditioner. Afterward, shut off all power. Use the breaker at the electrical panel to switch off the power to your unit. Go to the indoor unit, which is usually located in the attic and remove the cover to expose the evaporator coils. See if the sensor is either bent away from the coil or makes direct contact. If is doing either, both can be the source of the problem. You will want to put the sensor back in place. It needs to be close but should not make direct contact with or be too far away from the coils. If you’re not sure of the sensor’s proper placement, it is best to call a professional HVAC technician to complete the repairs.