Home Thermostats: A Guide

How much do you know about thermostats? If your home has an HVAC system, it has a thermostat. Whether your thermostat recently stopped reading the indoor air temperature or you just want to learn more about it, take a look at the top questions homeowners have about this HVAC component.

Why Does the HVAC System Need a Thermostat?

Without a thermostat, your home’s heating and cooling system wouldn’t know when to adjust the temperature. The thermostat reads or senses the indoor air temperature. This allows it to control your home’s HVAC system and turn the heater or central air conditioner on or off. Thermostat failure can leave your home hot in the summer and cold in the winter.

Are All Thermostats the Same?

While all thermostats help the HVAC system regulate the indoor air temperature, these devices do differ. The most common types are mercury contact bimetallic, mechanical contact, digital, and electronic programmable thermostats. Older homes with older HVAC systems may have mercury contact bimetallic or mechanical contact thermostats. Some older systems may also have digital (non-programmable) thermostats.

As the name implies, a mercury contact bimetallic thermostat uses two pieces of metal and a glass vial of mercury to sense and control the temperature. The mechanical contact device also has a bimetallic strip. Instead of mercury, this device uses a mechanical contact to control the temperature.

A digital thermostat works in a similar way to a mechanical contact device. But this thermostat has a digital display and electronic controls in place of a bimetallic coil.

Electronic programmable thermostats are newer options that, as the name says, allow you to program your HVAC system electronically. These digital devices let you choose times and days to raise or lower the temperature. This can help to regulate home comfort while using less energy.

What Are Smart Thermostats?

If you want to go a step farther than a traditional programmable model, smart thermostats give you a remote option and the ability to integrate heating and cooling with a larger whole-home system. You can control a smart device from an app on your phone or tablet. This makes it possible to monitor and change the indoor air temperature from almost anywhere.

How Do Thermostats Affect Your HVAC Costs?

As the control center of your heating and cooling systems, the thermostat has a significant impact on what you pay in HVAC-related costs. According to the U.S. Department of Energy, a seven to 10 degree Fahrenheit temperature change for eight hours a day can save many homeowners up to 10 percent annually in heating and cooling bills.

Again, if you have an older bimetallic or electronic digital thermostat, you won’t have a programmable option. Instead, you’ll need to manually change the thermostat for eight or more hours each day. But if you do have a programmable or smart thermostat, you can set the device and forget about temperature changes.

How Should You Maintain Your Thermostat?

Thermostats are often forgotten about – until they stop working. Don’t wait for your thermostat to fail. Simple maintenance tasks can extend the life of your thermostat or stop problems before they start.

Follow the manufacturer’s directions for care and routine cleaning. If you’re not sure how to properly maintain the device or can’t find the manufacturer’s instruction manual, talk to a professional. An HVAC contractor can inspect the thermostat and clean or care for it during pre-season service checkups.

Along with cleaning, the technician may also need to calibrate the device. Calibration helps the thermostat to accurately read the interior temperature, making it more likely your HVAC system will effectively cool or heat your home.

Do you need a new thermostat or a calibration? Contact Carrano Air HVAC Contractors, Inc, for more information.

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