A thermostat is the command center of your home’s heating and air conditioning system. So, when you’re struggling to heat or cool your living space properly, the source of the problem can sometimes be traced back to the thermostat.
The good news is that many common thermostat problems can be resolved with some basic troubleshooting, potentially saving you the cost and hassle of a service call. If you suspect your thermostat is the culprit behind your HVAC woes, follow our comprehensive guide to troubleshoot your broken thermostat and get your home’s comfort system back on track.
Steps for Troubleshooting a Broken Thermostat
These troubleshooting measures are simple, require minimal tools, and can often solve the most common thermostat-related problems.
Check the Power Source
Of course, your thermostat can’t communicate with your HVAC system if it doesn’t have any power. So, before doing anything else, make sure the device is connected to the proper power source.
Since many digital thermostats are battery-powered, you should replace the batteries if the screen is blank or flashes a “low battery” indicator. You can replace the batteries by locating the battery compartment — often on the side or by gently pulling the thermostat cover off its baseplate — and inserting a fresh set of batteries.
Even if your thermostat is battery-operated, it’s connected to your home’s electrical system through the HVAC unit, so it’s a good idea to check the state of your home’s circuit breaker. Go to the electrical panel and check if the breaker switch dedicated to your furnace and air conditioner has tripped. A tripped breaker will be in the “OFF” position or stuck in the middle. Flip it completely to “OFF” and then back to “ON” to reset it. If the breaker trips again immediately, you likely have a more serious electrical issue that requires a professional.
Is your thermostat connected to a furnace? Take note that some furnaces have a safety switch that looks like a standard light switch located on or near the unit itself. This switch can sometimes be accidentally turned off. Ensure it is in the “ON” position. Otherwise, your thermostat won’t be able to communicate with the furnace.
Review the Thermostat Settings
It might sound obvious, but incorrect settings are a very common cause of heating and cooling problems. For example, someone in the household could have changed them without you realizing it.
Make sure the thermostat is set to the correct mode for the season. It should be on “HEAT” during the winter and “COOL” during the summer. If it’s set to “OFF” or the wrong mode, it won’t activate the system.
Next, check that the thermostat is set to the right temperature. For heating, the set point needs to be higher than the current room temperature. For cooling, it needs to be lower. A simple test is to adjust the temperature setting by at least five degrees in the desired direction and wait a few minutes to see if the system kicks on.
Finally, verify that the fan setting is correct. “AUTO” should be on so that the fan only runs when the heating or cooling cycle is active. The “ON” setting causes the fan to run continuously.
Clean the Thermostat
Over time, dust, dirt, and other debris can accumulate inside the thermostat, interfering with its components and sensors. This is especially true for mechanical thermostats. With these non-digital devices, gently remove the cover and use a soft brush (like a small, clean paintbrush) or a can of compressed air to carefully clean the internal components. Be very delicate, especially around the coiled strips of metal and the mercury vial.
While digital thermostats are less susceptible to dust, the sensors can still get dirty. So, from time to time, remove the cover and gently wipe the interior with a soft, dry cloth or use compressed air to blow away any dust.
Consider the Thermostat’s Location
The placement of your thermostat can significantly impact its performance. An improperly located programmable thermostat, for example, can get false temperature readings, causing it to run improperly.
- Avoid Direct Sunlight: If the thermostat is in a spot where it gets hit by direct sunlight, it will read the temperature as being much warmer than it actually is. This will cause your air conditioner or heat pump to run excessively in the summer and may prevent your heater from turning on in the winter.
- Keep It Away From Heat Sources: Placement near lamps, televisions, kitchen appliances, or heat-generating vents can also lead to inaccurate readings.
- Ensure Proper Airflow: The thermostat should be on an interior wall, in a central location where it can sense the home’s average temperature. Avoid placing it in hallways with poor air circulation, behind doors, or in areas subject to drafts from windows or doors.
When Is It Time for a Thermostat Replacement?
While troubleshooting can fix many issues, it’s important to note that thermostats don’t last forever. There will come a point when a repair is no longer practical or cost-effective, and a replacement is the better option.
Here’s how to know when your thermostat needs more than just basic troubleshooting:
- Age: The average lifespan of a thermostat is about 10 to 15 years. If yours is older, its components may be worn out and unreliable.
- Persistent Issues: If you find yourself constantly adjusting the thermostat, or if the troubleshooting steps only provide a temporary fix, it’s a strong indicator that the unit is failing.
- Inaccurate Temperature Readings: Does the temperature displayed on the thermostat not match the actual feel of the room? If your home feels much warmer or cooler than the reading, the sensor is likely faulty.
- HVAC System Short Cycling: If your furnace or A/C turns on and off in rapid succession without completing a full cycle, a faulty thermostat could be sending incorrect signals.
- No Power or Unresponsive Display: If you’ve replaced the batteries and checked the breaker, but the screen remains blank or the buttons are unresponsive, there may be something wrong with its electrical wiring or it may have simply reached the end of its life.
Let Alltemp Air Solve Your Thermostat Problems
Troubleshooting a thermostat that isn’t working can often resolve common HVAC issues, but it’s not always a simple fix. If you’ve gone through these steps and are still unsure what’s going on with your system, or if you need help determining whether a repair or a replacement would be the most cost-effective solution for your home, call in the experts at Alltemp Air.
Our heating and air conditioning repair technicians have the knowledge and tools to accurately diagnose any thermostat or HVAC problem. We can identify the root cause of the issue, perform professional repairs, and provide expert recommendations on the latest thermostat technology, all in an effort to keep your home comfortable.
Reach out today to schedule a thermostat service in Lewes, DE, or one of the surrounding areas!
