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5 Signs of a Bad Thermostat

Sometimes, when your heating or cooling equipment fails to satisfy your comfort demands, the source of the problem isn’t the HVAC system at all — it’s a faulty thermostat. Malfunctioning thermostats can manifest in many different ways, and it’s important to know what signs to look out for so you can plan any necessary replacement services and avoid disruptions in your indoor comfort.

In this blog post, we’ll explore some of the most common signs that indicate your thermostat may need repair or replacement so you can make the most informed decision for your home comfort needs.

1. Your HVAC System Won’t Start Up

If you set your thermostat to the desired temperature, but your HVAC system never turns on, there could be a wiring defect at play. In some cases, this defect may cause the thermostat to lose connection with your heating or cooling system, resulting in a failed communication to turn the system on.

Alternatively, failed system startups could point to a failed temperature sensor. When your thermostat’s temperature sensor is malfunctioning, it could misread the temperature in your home as already being at the desired level, preventing your HVAC system from turning on.

2. Your HVAC System Won’t Shut Down

In the same way that a malfunctioning sensor or wiring defect can cause startup failures, these thermostat issues can also cause your HVAC system to remain on longer. This can result in higher energy bills as your heating and cooling equipment remains on for longer than necessary.

Other times, shut-off failures could be triggered by an improperly programmed thermostat. If your thermostat is set to shut off at a temperature higher or lower than you originally intended, it could cause your heating or cooling system to remain on longer than needed.

3. You Notice Erratic Temperature Fluctuations

Dramatic temperature fluctuations can indicate that your thermostat isn’t working properly. If you notice that your home is suddenly too hot or cold without adjusting the thermostat settings, your thermostat may require a professional inspection to diagnose and repair.

There could be several underlying reasons for why your thermostat is causing your home to become too hot or too cold, including:

  • Calibration Issues: Thermostats must be calibrated correctly to measure and control your indoor temperature accurately. If it’s improperly calibrated, it can lead to inaccurate temperature readings and inconsistent heating and cooling.
  • Sensor Problems: Thermostats rely on temperature sensors to detect indoor temperatures. Malfunctioning or dirty sensors can provide inaccurate readings, leading to severe temperature swings.
  • Electrical Issues: Faulty wiring or electrical connections can disrupt the thermostat’s ability to communicate with the HVAC system effectively, causing temperature irregularities.

A woman tries to re-set her faulty thermostat

4. Your HVAC System Makes Strange Noises

In certain cases, the loud noises you hear from your HVAC equipment during operation may indicate a problem with your thermostat rather than the heating or cooling system itself. If you hear rumbling, boiling, or knocking sounds coming from your furnace or air conditioner, it could be a sign that the thermostat is not regulating your indoor temperature properly.

5. Your Home Has Hot & Cold Spots

While hot and cold spots are more indicative of a problem with your HVAC unit, such as a clogged air filter or obstructed ductwork, this can also be a sign of a failing thermostat. As aforementioned, a thermostat needs to be properly calibrated to work correctly. If not, you may notice areas in your home that are significantly hotter or colder than others.

Upgrade Your Thermostat Today!

Is your thermostat showing signs of degraded performance? Huge Heating & Cooling offers the repair and replacement solutions you need to restore reliable, long-lasting comfort to your home. For nearly 60 years, we have offered the superior comfort solutions that Northeast Ohio homeowners trust to keep their systems running smoothly.

Trust our team to get your thermostat back in working order fast. Call us at (440) 234-4157 to request thermostat repair or replacement now!

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