Why Does Thermostat Goes Above Set Temp? Complete Fix Guide

Why does thermostat goes above set temp? If you’re experiencing this situation, there is something wrong with your current setup.

If your thermostat’s current temperature readings cannot match that of the ones you set, you’re not going to have the most comfortable of situations.

There is something wrong with your thermostat settings, or your entire system needs an upgrade.

Whenever your thermostat keeps going to up 85 or more, you’re probably looking at one with faulty wiring. You want to make sure the wires are set properly, so your thermostat can function correctly. Installing your thermostat in the wrong place in your home can also cause this problem.

Let’s take a closer look at the possible causes of this problem before we move on to the comprehensive troubleshooting steps.

Why Does Thermostat Keeps Going Up

The issue with your thermostat not reaching your desired temperatures comes from several sources.

We recommend checking your thermostat installation as any dirt or dust can affect the readings. You will want to open it up to determine the culprit of this error.

Here are the issues that have likely occurred with your thermostat and caused this problem.

1. Dirty Thermostat

Your thermostat comes with probes that monitor the current temperatures. Dust and dirt can block the probe and result in a wrong reading that will affect your thermostat’s performance.

2. Outdated Software

Smart thermostats run on complicated software that needs to be updated often. If you stick to using older and outdated ones, there’s a tendency that it will affect its overall performance.

3. Wiring Problem

Your thermostat wires needs to be connected to the right terminals. Not doing so can result in power delivery issues that can cause this issue to occur.

4. Wrong Location

Placing your thermostat in the wrong spot in your home means it will not give you accurate readings.

Now that you have a good idea of the problems with your thermostat, you’re now ready to proceed to the next steps.

You’re now better equipped to resolve this issue once and for all!

How to Fix Thermostat Goes Above Set Temp

If this is the first time that happens to you, you want to refresh your thermostat before doing anything else.

Power it down, then turn the breaker for your HVAC and thermostat off. Wait for a few seconds, then turn it back on.

Doing this can quickly resolve minor problems, so you don’t have to waste more of your time.

If the refresh does not work, here are the next steps you need to do to finally resolve this issue:

Solution #1: Make Sure Your Thermostat is Clean

If you have not opened up your thermostat for some time and you’re now experiencing this issue, it’s about time you clean it.

Dirt and dust can block vents and cause your temperature probes to read differently.

You’ll need to get rid of the dust, dirt, and grime and see if your thermostat hits your set temps.

Here’s how to clean your thermostat:

1. Remove the cover of your thermostat.
2. Dust the inside with a soft, clean brush.
3. Replace the batteries with fresh ones.
4. Replace the cover of the thermostat.
5. Turn it on and check the temperature readings.

Note: Make sure to clean your thermostat regularly as it’s one of the main causes of inaccurate temperature readings.

Solution #2: Recalibrate Your Thermostat

Cleaning is one thing, but making sure your thermostat’s probes are up to snuff is a completely different matter.

You want to make sure that your thermostat’s temperature sensors are accurate.

You can recalibrate your thermostat to make sure that your readings are what they’re supposed to be.

Here’s how to recalibrate your thermostat:

1. Get a room thermometer and place it near your thermostat.
2. Turn on your thermostat.
3. Wait for about 15 minutes.
4. Compare the readings between the two devices.

Pro Tip: There should not be a difference of more than 1 or 2 degrees between your thermometer and thermostat.

Alert: You might want to contact a professional to recalibrate your thermostat if you find out that it’s off by a few degrees.

Solution #3: Check Your Thermostat Wiring

Wiring your thermostat can get tricky. However, modern thermostats come with a wiring guide that’s easy to follow.

You can check this against your current wiring to see if there are any inconsistencies.

You will only need to check for corrosion on the wires for better connectivity for the most part.

Here’s how to check your thermostat’s wiring:

1. Open the cover of your thermostat.
2. Compare the current wiring against your thermostat’s guide.
3. Tighten loose wires on the panel.
4. Check for corroded wires.
5. Clean the contacts with a Q-tip moistened with rubbing alcohol.

Note: Use rubbing alcohol at least 70% to avoid moisture build up after you clean the contacts.

Solution #4: Change the Location of Your Thermostat

You want your thermostat to be representative of the temperature levels inside your home.

If your thermostat is located in a place that receives a lot more heat than the rest of your home, you can be sure that it will not give you an accurate reading.

The good news is that you will be able to move your thermostat inside your home easily. All it takes is a couple of basic tools.

Here’s how to move your thermostat:

1. Turn off your thermostat, including the breakers.
2. Remove the front panel and take a picture of the current wiring.
3. Disconnect the wires and remove the back panel from the wall.
4. Drill a new hole and pull the wires through it.
5. Attach the wall panel and reconnect the wires.

Tip: Make sure to place your thermostat on an interior wall and away from direct sunlight, vents, hallways, and doors.

Solution #5: Update Your Thermostat Software

Outdated software is one factor that can cause this error, especially with modern smart thermostats where you can control them using your phone.

Certain settings can unexpectedly freeze, and what you see on the panel may not be the one set on the app.

If this is the case, you will need to check if an update is available for your thermostat so you’ll be able to resolve this issue.

Here’s how to update your thermostat to the latest version:

1. Open your smart thermostat’s settings.
2. Go to About.
3. Select Version or Software.
4. Choose Update to start the process.
5. Wait for your thermostat to complete the process.

Note: For other thermostat brands like Honeywell and others, you will be able to update the software by opening the app, going to settings, then selecting update.

Thermostat Still Goes Above Set Temperature?

If none of these steps help resolve your problem, it’s likely that your HVAC system and the thermostat are not the right sizes for your home.

The capacity could be too small that it’s unable to reach your set temperatures.

If this is the case, you can look to upgrade your entire system by contacting a professional for assistance.

Replacing a faulty thermostat is also one of the options you need to consider.

Read Next: Thermostat Set to Cool But Heating? – (Easy Fix)

Bottom Line

Now that you know why your thermostat goes above set temp and the steps to fix it, you can get your home to comfortable levels in no time.

For more advanced steps, it helps to have a professional with you since you will be dealing with live electricity.