Thermostats are among the most important appliances in our homes. They let us dial in temperature and humidity settings for maximum comfort. Modern thermostats also help our systems be as efficient as possible and thus save us money. As thermostats become more sophisticated, there is a lot that can go wrong with them. If you experience thermostat troubles, you should contact your local HVAC technician to diagnose and fix the issues. But let’s explore some of the most common problems you may experience and why they could be happening.

Thermostat Turned Off

If you’re HVAC isn’t running, you may look at your thermostat and notice that it has turned off. This is a very common issue with a wide array of causes. The first thing a technician will do is remove the faceplate and blow out any dust. There is a series of electrical connections behind the faceplate. Dust accumulation can disrupt them and cause a fault.

If that isn’t the issue, it may be that the thermostat has failed. Your technician will first check to ensure there isn’t a tripped circuit breaker. The technician will then test the thermostat fuse. If it has blown, this is an easy fix with a replacement. Next, the tech will test the circuit board. Outright thermostat failures aren’t common. These devices last a long time. But all of them will fail eventually.

A lack of source power is a potential cause as well. The typical HVAC setup provides power to the thermostat from two sources: the HVAC system itself and a backup battery. If your thermostat runs on battery power alone, then the battery is dead. If your thermostat receives primary power from the HVAC system, the system has an issue. This is often as simple as improper drainage. The drip pan is full, which trips the HVAC system, and the thermostat turns off.

Thermostat Is Beeping

Many modern thermostats make a beeping sound like a smoke alarm. The beep notifies you that the backup battery is running low or has died. The fix is simple. You just need to replace the battery. Some thermostats use AAs or AAAs. Others use flat batteries, which are also known as coin and cell batteries.

Thermostat Screen Turned Another Color

A common thermostat feature is to set text and background color. If the color changes, first check that someone in the house has not altered the setting. If you wake up in the middle of the night and notice the screen is gray, this usually means the battery is recharging. It can also indicate diagnostics and other advanced features. Some thermostats will go blank or blink to provide a similar indication.

Thermostat Not Adhering to Programming

Software issues in programmable and smart thermostats are very uncommon. In rare cases, your technician may need to perform a firmware update. The most common cause of programming issues is an override. Most programmable thermostats have a hold mode. That mode lets you suspend programming. You should also check that you haven’t switched the thermostat into vacation mode. You may have also switched the thermostat into a profile that has different programming or none at all.

System Won’t Turn On or Isn’t Blowing Air

It’s common in modern systems for the thermostat to turn off when there is a systemic problem. This indicates to you that there is an issue that a technician needs to diagnose and fix. With an older thermostat and/or HVAC system, this may not be the case. The first thing a technician will check is the HVAC filter. If the filter is too clogged, the pressure in the system can trip it. The next step would be to ensure that the thermostat and HVAC system are fine independently of each other as discussed earlier. If that is the case, it can be an issue with the electrical or network system connecting them.

HVAC System Keeps Running

How long your HVAC system runs is called a cycle. Cycles can be adjusted for efficiency and performance reasons. If an HVAC system runs for what feels like too long, replace the HVAC filter. If it continues running, call a technician. This is likely an issue with the system and not the thermostat itself. However, some smart thermostats do allow you to adjust cycle times. It is possible that the setting is wrong or that a malfunctioning thermostat is causing this issue.

HVAC System Turns On and Off Frequently

Long cycling refers to an HVAC system running too long as discussed above. Short cycling refers to a system that doesn’t run long enough. A homeowner may refer to this as turning on and off frequently. Again, this is often due to a dirty filter. In the case of an AC or heat pump, it could be due to a refrigerant leak. A malfunctioning thermostat can also cause short cycling. Replace the batteries and power cycle the thermostat. If the issue persists, call a technician.

Not Comfortable Despite Reaching Setting

If your home is uncomfortable despite reaching your temperature setting, this is often a thermostat issue. Check temperature via another thermometer. If the readings match, it may be a humidity issue or another problem. If the settings do not match, it means that the thermostat calibration is off. Older thermostats have a manual calibration screw. Digital thermostats have a calibration mode. It’s generally best to have a technician calibrate your thermostat and ensure that the setting is precise.

Incorrect Readings

If a thermostat is displaying an incorrect temperature, it may mean that the sensor is bad. Your technician can replace the sensor, and the reading will be right once again. This issue isn’t limited to temperature sensors. It can be the case with a hygrometer or barometer as well.

Thermostat Positioning

Improper thermostat positioning is a problem that can manifest in a wide range of ways. A thermostat, for instance, should never be in direct sunlight. If it is, your AC will run a lot longer than it should. For similar reasons, a thermostat should be no closer than 5 feet to any door. If this is the issue, one potential solution is to have your technician reposition it. Another is to upgrade to multiple sensors. If you have a thermostat with a mercury bulb, it can also be that the thermostat is not level.

Your Local Thermostat Pros in Vacaville

If you’re experiencing thermostat problems, Cozy Home Services is here to help. We have decades of experience and serve homeowners throughout Vacaville and the surrounding areas. Our technicians install, maintain, and repair heating and cooling systems.

We have IAQ experts who specialize in air purifiers, dehumidifiers, and humidifiers. Our electricians upgrade electrical panels and design and install solar systems. We also have plumbers who clean drains, detect leaks, repair sewers, and install water heaters and water softening systems. Call today or contact us online to schedule an appointment or with any questions about the products and services we offer.