Is it normal to have the thermostat show a higher indoor temperature than what it is set at?

Author: Dr. Gillian Bernier  |  Last update: Wednesday, February 4, 2026

A thermostat turns on your heating system by determining the temperature of its environment with a sensor. If your thermostat's sensor isn't functioning properly or at all, the result is a room temperature that's either higher or lower than your thermostat setting.

Why is my thermostat reading higher than the setting?

Thermostat Location: If the thermostat is placed in a location that is exposed to direct sunlight, near heat sources, or in a drafty area, it may read a higher temperature than the actual average temperature of the room.

Why is my house hotter than the set temperature?

Your HVAC system isn't sized properly

An HVAC system that's too large for your house will cool your home unevenly. It will only cool some rooms off and then shut off versus cooling down the entire house. On the other hand, an HVAC that is too small will have to work above its capacity to cool down a house.

Why does my thermostat setting not match my home's temperature?

Dirty or worn flame sensors, blower motor problems, clogs in the condensate lines, and electrical issues are some of the many problems that can leave your HVAC system failing to deliver the temperatures you've programmed in your thermostat.

Why is my AC thermostat set at 74 but reads 78?

That usually means that the thermostat sensor is faulty. You have two options. Change the thermostat, or simply ask for a higher temperature. So press the up arrow a few times to change the 74 to 78 and you should feel warmer.

Why is my thermostat reading higher than setting?

Why does my thermostat say it's hotter than it is?

If your thermostat is not reading correctly, it might be due to a dirty or faulty sensor. A quick fix could be to gently clean the sensor with canned air to remove any dust buildup. However, if problems persist, replacing the thermostat could be the next step.

How cool should my house be if it's 100 outside?

For many of us, 70 degrees is the ideal indoor temperature, but when it is close to 100 degrees outside, your AC unit will be working quite hard to meet these expectations. Consider setting your thermostat at 75 degrees to 80 degrees in your home if the outside temperature is approaching triple digits.

Why is my room temperature higher than my thermostat?

Check the Power Sources

Swap out the batteries and see if that corrects the thermostat readings. If the batteries are good, then look at other power sources in your home like blown fuses and tripped breakers. If you suspect that the issue may be a breaker or fuse, you may need to hire an electrician to fix the problem.

How do I know if my thermostat is inaccurate?

The Room Temperature and Setting Don't Match

If, no matter how often you set the thermostat, the setting and room temperature never match, the unit has likely lost accuracy. The cause may be a calibration issue. Or, the unit may have a wiring problem affecting its function and power supply.

Why is my AC set at 75 but reads 77?

Clean the Thermostat

Sometimes, when the room temperature doesn't match the thermostat setting, the problem could be dirt buildup on its interior parts. A dirt coating around the inner components may create excess heat and cause the thermostat to give the wrong readings.

Is 82 too hot for a house?

In general, 80 degrees is too hot for a house if people are inside. However, if people aren't home during the day or for vacation during the summer, an indoor temperature of 80 degrees can save energy until you return and lower the temperature.

Where is the thermostat sensor?

Locate the sensor, which is a small, round component usually positioned near the bottom of the thermostat. It may be labeled as “sensor” or “thermistor.” Using a soft brush or a can of compressed air, carefully clean the sensor to remove any dust or debris that may have accumulated on its surface.

Why does my thermostat keep raising the temperature?

If you try to resolve the issue after checking for default programming, energy-saving programs, old batteries, and even if someone has been changing the temperature in your home it may be time to contact a professional. There may be an issue with old wires or software.

How do I make sure my thermostat is accurate?

Checking the calibration of your thermostat is easy and should be done once a year, generally in the fall. To do so, locate your home's thermostat and tape an accurate thermometer on the wall next to it. Wait 15 minutes and check the temperature reading on both devices.

Why is my central heating thermostat showing the wrong temperature?

One of the most common reasons that your thermostat is incorrectly reading your home's temperature is that the temperature sensor is malfunctioning or has failed completely. Replacing a temperature sensor can be very difficult, so there are a few things you should try before you schedule a replacement.

What is the highest temperature you should set your thermostat?

We recommend the following as the best thermostat settings:
  • For warmer times, set your thermostat at 78° F during daytime. Set it to 86° F if you leave the house.
  • For cooler times, set your thermostat to 68° F while you're at home and awake. Lower it to 65° F when you sleep.

How can you tell if your home thermostat is not working properly?

7 Ways to Tell Your Thermostat Is Broken
  1. The Thermostat Has No Power. ...
  2. The AC or Furnace Won't Turn On. ...
  3. The Heater or AC Won't Turn Off. ...
  4. The Thermostat Reading Doesn't Match the Room Temperature. ...
  5. The Thermostat Doesn't Respond. ...
  6. The HVAC System Is Short Cycling. ...
  7. The Thermostat Forgets Programmed Settings.

Why does my thermostat say 70 but feels colder?

If you're cold even though your thermostat indicates you shouldn't be, your furnace likely isn't the problem. In most cases, it's working just fine. It's your home that needs attention. Lack of insulation, severe air leakage, and/or unbalanced ductwork are frequently to blame.

How do I know if my thermostat needs calibration?

Inconsistent home temperatures and high energy bills are telltale signs your thermostat may need calibration. Thermostat calibration, as well as boiler maintenance, are essential components of HVAC systems. Properly calibrating your thermostat ensures more precise temperature control and energy efficiency.

Why is my thermostat not reading room temperature correctly?

At the heart of your thermostat's functionality is its temperature sensor. If your thermostat is not reading correctly, it might be due to a dirty or faulty sensor. A quick fix could be to gently clean the sensor with canned air to remove any dust buildup.

How do I know if my thermostat is reading the correct temperature?

Leave both units in place for another 20 minutes, and check the readings again to see if the readings are the same. If the readings between your thermostat and thermometer are still different, you likely have a malfunctioning thermostat and there may be an issue impacting thermostat accuracy and efficiency.

How do you calibrate a room thermostat?

Using an appropriately sized screwdriver, turn the calibration screw to open the contacts. Wait a few seconds, then turn the screw to close the contacts. This will reset the contacts and make sure a bad connection wasn't causing your thermostat to become uncalibrated.

How cool should my house be if it's 110 outside in summer?

Just because the outdoor temperature is above 100, the Ideal temperature to set your AC unit to doesn't change — it's 78 degrees. Higher temperatures in the home are to be expected when the weather is hotter than usual, but your thermostat can still be set the same as if it were a lower temperature outside.

What is a good indoor house temperature?

In general, the ideal room temperature and your home for both efficiency and comfort fall somewhere between 68° and 76°F.

How long should it take to cool a house from 80 to 72?

Cooling a house from 80 to 72 degrees is a common goal for many, especially during the peak of summer. On average, this process takes roughly two and a half to three and a half hours.

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