Troubleshooting Thermostat Problems Keeps Your Temperature Settings in Check
Troubleshooting Tips for Common Thermostat Problems
If your home’s central A/C or heating system is malfunctioning and can’t keep your indoor spaces at a comfortable temperature, you know you’ve got a problem. While it could be an issue with the HVAC system itself, your first course of action is to check your thermostat. Luckily, thermostat issues are typically easier to diagnose and correct, and a few simple troubleshooting techniques could solve the problem.
Here, we’ll take a look at how homeowners like you can test your thermostat, find the source of the issue, and use our thermostat troubleshooting tips and advice to get it resolved.
How Does a Thermostat Work?
A thermostat works by sensing the temperature in your indoor environment, then comparing that with the preferred temperature you’ve set. When the temperature is cooler than the setting, the thermostat triggers the heat pump or furnace to start up. When the temperature is warmer than the setting, the air conditioner or cooling system kicks on.
In older thermostats, the sensor that detects the indoor temperature is made up of different metals that expand and contract, which triggers the HVAC system to start. More modern thermostats use an electric or infrared sensor. The latest thermostats are digitally operated, and use microprocessors to detect temperatures and signal the heating or cooling system to run.
Testing Your Thermostat Settings
If you suspect a problem with your thermostat, your first course of action is always to run a test. This is easiest in smart thermostats, where the test function is built in. In your thermostat’s settings, you should be able to navigate to a system test and follow the on-screen instructions.
For older, non-programmable thermostats, there are several ways to perform a test. You can use a tool like a multimeter to measure the thermostat’s voltage, or find a freestanding thermometer to see if the reading on it matches the one on your thermostat. The simplest test requires two people. Have someone positioned at the furnace or air conditioner, while the other person stands near the thermostat, and adjusts the temperature to heat or cool. The first person can then indicate whether or not the A/C or heat kicks on.
How to Reset Your Thermostat
If you’ve tested your thermostat and you believe there’s a problem, your next step is to reset it. Oftentimes, that will refresh the system and get it back to operating on a normal cycle. Here’s how to reset a thermostat:
- Determine whether your thermostat has a reset button. These are often recessed and require a pin or paperclip to depress. If your thermostat has this feature, you can simply press reset and allow it to restart.
- If there is no reset button or if that process did not work, shut off power to the thermostat, and make sure it’s turned off.
- Find your circuit breaker that’s connected to the thermostat and flip it. Wait for 30 seconds, and then flip it back on.
- Turn the thermostat back on, and make sure it’s set to the appropriate heating or cooling function, and is at a temperature that will trigger it to turn on.
- Wait a moment to see if your heat pump, furnace, or air conditioner engages. If not, you can try changing the batteries on the thermostat or read through your thermostat manual.
If this process still doesn’t result in a functioning thermostat, you can look through this list of thermostat problems and troubleshooting tips to fix them.
Common Thermostat Issues and How to Troubleshoot Them
You rely on your thermostat more than you know. Even if your HVAC system is working perfectly, it won’t be able to heat or cool your home if the thermostat is malfunctioning. A thermostat replacement is one option, but before you go that route, you can learn about the common issues found in thermostats, and try to troubleshoot yourself before calling in an HVAC professional. Here are some of the top problems found in thermostats:
Thermostat Isn’t Signaling HVAC to Turn On
If you’ve already taken the steps listed above, you’ve checked whether the HVAC system and thermostat are getting power. Often, the problem is as simple as a tripped circuit breaker or blown fuse. However, if the thermostat is getting power and you’ve attempted to change the batteries, there could be another issue.
Over time, your thermostat’s inner workings can get coated in dust, which can interfere with its mechanical and electrical operations. To determine if a dirty thermostat is the issue, open the thermostat casing and clean it out with a small brush.
If the wiring is loose or disconnected, try reconnecting it (make sure the power is off before handling anything electrical). Call a professional HVAC technician if you can’t address the wiring problem.
Thermostat Temperature Doesn’t Match the Room Temperature
Make sure your thermostat is level. If it’s not level or has been incorrectly installed, it can offset the setting and calibration. Use a level tool to ensure the thermostat is level, and check if that corrects the issue. It is also good practice to keep the thermostat clean and clear of dust.
Thermostat Shuts Down Suddenly or Doesn’t Shut Off
A clean-out is a good first step to see if that corrects the problem, but if it doesn’t, there may a deeper issue. In a mechanical thermostat, there might be a malfunction in the anticipator, which could force a system shutdown for no apparent reason or keep it running even after the desired temperature has been reached. In this case, you’ll want a proper diagnosis from a qualified service provider to determine your next steps.
HVAC System Cycles on Too Frequently
Short cycling is a common issue for HVAC systems that are linked to faulty thermostats. When the temperature reading is inconsistent, it can trigger the HVAC unit to cycle on and off more frequently. If you don’t find an obvious problem with your thermostat, check for other potential issues, like a clogged air filter or blocked ductwork. Be sure any outdoor units are clear of debris. If the problem persists, you may need to contact an HVAC professional to recalibrate your home thermostat.
Surprisingly High Energy Bills
You may not have heard or noticed the HVAC system short cycling, but you’ll be sure to pay attention when you get your utility bills. If you see an unexpected spike in energy costs that you can’t directly link to the outdoor temperature, your thermostat could be to blame. As with other thermostat issues, it’s best to first attempt resetting and cleaning the thermostat before you seek out a professional opinion. If possible, look back at previous energy bills to get an understanding of how cost and usage changes over time, so you know if there’s a real problem, or if it’s a natural fluctuation.
Home Isn’t Comfortable After Thermostat Installation
If you’ve recently had a new thermostat installed but your home still doesn’t maintain a consistent or comfortable temperature, or if you’ve always had less-than-ideal temperatures but thought that was the norm,make sure the thermostat is located in a good spot. It should not be placed on a wall that receives direct sunlight or cool drafts. If it’s responding to atypical conditions, it won’t properly cool or heat other parts of the house. The solution could be as simple as closing the blinds or shades to reduce sunlight, or blocking a drafty area. As a worst-case scenario, you may need to have the thermostat moved to a new, central location where it can get a more accurate reading.
Outdated Thermostat
An old thermostat can still work surprisingly well, but like anything, they do have a limited lifespan. Old thermostats actually tend to last longer, up to 35 years. An analog, non-programmable thermostat isn’t subject to changing technology, so it can persist for decades longer than programmable or smart thermostats. They tend to need replacing once a decade or so, primarily due to new innovations and upgraded energy efficiency. If you have an analog thermostat older than 35 years, or a digital thermostat older than 10, it may be time for an upgrade. If you’re shifting from analog to digital, you’ll likely want to replace your old thermostat with something that integrates with your other smart home devices.
Smart Thermostat Doesn’t Turn On
Smart thermostats and programmable thermostats are fantastic for saving energy and lowering utility bills, but they sometimes come with their own unique set of issues. If you’re having issues with a smart thermostat, first be sure that your WiFi is on and the device is connected. If you see a blank screen and your HVAC unit isn’t kicking on, that could be the problem. Also be sure to check your thermostat’s compatibility with your HVAC system and its connection to your router. You can try to reset your WiFi and see if that resolves the issue, or disconnect and then reconnect all your smart home devices.
Preventive Maintenance and Troubleshooting Tips to Avoid Ongoing Issues
The number one action you can take to keep your home comfortable no matter the weather is to maintain your thermostat (and the rest of your HVAC system). Preventive thermostat maintenance includes:
- Cleaning: Make sure to regularly remove dust and debris on both the exterior and interior of your thermostat. Remove the outer casing and blow out the dust or use a soft brush to clear it out.
- Replacing batteries: Whether or not you think fresh batteries are needed, you’ll get the most out of your thermostat if you replace them regularly. Dead batteries can corrode and cause even bigger problems. Put in new batteries once a year — schedule it in the same window you replace your smoke detector batteries to make it easier to remember.
- Checking connections: Every so often, visually inspect your thermostat’s internal workings and look for loose wires and other connectivity issues. Tighten up the electrical connections to ensure nothing else comes loose.
- Calibration: Many thermostats have a built-in calibration function. You should be checking and running this recalibration at least twice a year — once before the heating season, and again before the cooling season.
- Scheduling maintenance: Make sure your thermostat is ready for whatever weather is ahead by making it part of your routine HVAC maintenance plan. Your HVAC technician should test your thermostat at your annual tune-up.
Dial Up the Comfort with Help from Airtron
Even minor thermostat issues can turn into major headaches if left unchecked. Make sure to stay on top of potential problems by making thermostat maintenance part of your routine. The pros at Airtron can help. With our Essential HomeCare program, we’ll check out your thermostat as part of your included tune-up — plus we’ll make sure both your heating and cooling systems are operating at peak condition, so you stay comfy all year long. Contact us today to get started!
