AC Troubleshooting: Common Thermostat Problems and Fixes

The ideal home temperature is around 18-24 degrees Celsius for most healthy adults across Canada. To ensure this temperature this summer, having a good HVAC system and accurate thermostat is essential for all individuals and families. This means understanding and troubleshooting any thermostat problems that may arise.

But what are the most common issues that people face with their thermostat function? Read on to answer this question and to get some tips on troubleshooting these common issues.

The Thermostat Is Too Old

Thermostats don’t last forever. In fact, their average lifespan is only about 10 years. In some cases they may decline slowly or become buggy or less reliable over time before becoming totally unusable. But this decline can be difficult to see if the thermostat seems to be working fine.

If you’ve had your thermostat for a decade, that’s a sign to change it in and of itself. You’ll want to talk with a reputable HVAC company about installing a replacement or you can also buy one online and install it yourself if you have the basic skill and patience.

This has the added benefit of getting you the latest AC-related technologies so you aren’t running on something outdated.

The Thermostat Placement Is Off

Thermostats’ primary purpose is to give you an accurate temperature reading in your home. Smart thermostats also regulate the temperature of your home consistently, running on a pre-set schedule.

However, your thermostat can’t do this if you don’t position it correctly. If the sun is shining on it, the thermostat is naturally going to give you too high a temperature; drafts will bring the reading down too far.

This also causes a practical issue because the thermostat will turn your HVAC off and on at the incorrect times. Your home will never be the right temperature. If you notice that the reading is inaccurate, check its placement.

Some newer smart thermostats claim to be able to adjust for this, although it’s usually best to install it in a proper location to begin with. Moving your thermostat may require the help of a professional however.

You want to mount the thermostat about 150 centimeters above floor level so that it’s away from sources of heat or coldness. This ensures accurate readings… and you don’t need to pay a cent!

Furthermore, you want the thermostat to be near your main living area so it is taking accurate temperature readings.

Many smart thermostats can also be configured with additional sensors placed in other rooms to provide better temperature sensing.

You Aren’t Getting an Accurate Temperature Reading

Sometimes, your thermostat won’t give you an accurate reading of the temperature inside your home or commercial space. This is sometimes true regardless of its placement.

For example, you may know that it’s 25 degrees C inside your house but still see a higher or lower reading. This is a surefire sign that you need a thermostat replacement ASAP, as the sensor may be defective.

You also need to make sure that your thermostat can be cranked up to the appropriate temperature for comfort. If you can’t get it there, you may have it on the wrong setting. Make sure that you turn it to the cool setting rather than fan or off.

Get Quotes

How soon are you looking to buy?*

Urgently!

Next few weeks

Not sure yet

A Broken Display

If your thermostat is displaying incorrect temperatures, you at least know that it’s functional. You may need to change it for accuracy, but it still is at least in part doing its job. However, sometimes the screen might just shut off and display nothing or it may be less responsive.

If you aren’t seeing any numbers on your thermostat screen, check to make sure that the batteries in your thermostat aren’t dead. You might just need to change them out so that your thermostat functions again.

If that doesn’t work, you may have a wiring problem that requires an expert hand. It’s possible that you haven’t appropriately connected it to the HVAC or to your home’s electrical source. You also may need to replace it in some cases.

The Air Conditioner Never Stops Running

A thermostat is intended to send a signal to your HVAC system when the room reaches the desired temperature. This means that your air conditioner should eventually switch off (and come back on again in a little while).

A constantly-running air conditioner can cause overheating and other dangerous problems. More likely, though, you’ll just ruin the AC unit by overworking it. Overworked air conditioners also have the added downside of higher electric bills.

Thermostat malfunction is a common reason that the AC continues running all day. It simply may not send signals for it to stop running. You’ll need a thermostat replacement in these scenarios, so you would need to enlist a professional for assistance.

Note that the issue may also be with your air conditioner itself, something like a faulty control board may be to blame.

Try our A/C breakdown & repair cost calculator to help diagnose issues.

Your Home Has Uneven Temperatures

When you buy a new thermostat, the factory has calibrated it to make sure that it gives accurate temperature readings throughout your home. As time goes by, this calibration naturally alters and the thermostat becomes less and less efficient.

The result of this is uneven temperatures throughout your home or constantly fluctuating temperatures. If you notice these temperature inconsistencies, you should have your entire system checked by a professional to diagnose the cause.

If you don’t catch this problem, you may wind up with short-cycling issues. This is both uncomfortable and costly, so ask an expert to check on your thermostat’s calibration.

Strange, Inconsistent Readings

If your air conditioner is making strange clunking sounds while it runs, it likely requires some cleaning or may have a malfunctioning component.

Keeping your thermostat clean and dust-free, especially around sensors, can help reduce temperature reading inconsistencies.

This is luckily an easy fix. All you need to do is open your thermostat case and brush debris off its interior with a soft cloth. You should pay careful attention to clearing the contacts before turning on your AC this summer.

Resolve Common Thermostat Problems Today

While thermostat problems can be a thorn in your side, they usually are simple enough to resolve. Now that you know how to solve some of the most common problems with HVAC systems, it’s time to do something about your thermostat malfunction.

Our experts are committed to helping you stay comfortable this summer. That’s why we have verified licenses and insurance policies to back up our high-level knowledge of air conditioning units. Request a quote for a fair and transparent estimate on the price of your maintenance.

Get Quotes

How soon are you looking to buy?*

Urgently!

Next few weeks

Not sure yet