Updated July 24, 2023
The right thermostat settings can keep your home comfortable, maintain safe humidity levels and lower your energy bills. However, finding the most effective thermostat setting is often easier said than done. It gets especially tricky when you are living in a multi-story home. Bardi Heating, Cooling & Plumbing in Atlanta, GA, knows how important these settings are. Here are some things to know when trying to find the right thermostat settings.
Understanding How Multi-Story Designs Affect Your Home’s Temperature
When deciding on how to set your thermostats, you need to remember one simple principle. Heat always rises. This ends up greatly affecting the way your air conditioning system works.
Many people assume that they should just set each thermostat to their preferred temperature for the floor and leave it alone. However, this ignores the fact that air travels between the stories of your home. Hot air is always trying to go to the upper story while cold air is trying to sink to the lower stories. If you set all thermostats to the same temperature, your upper story air conditioner will work overtime in the summer while all your cold air will fall to the lower levels. Likewise, your lower-story heater will have to work too hard in the winter while the hot air instantly heads upstairs.
The fact that height affects temperatures so much can lead to all sorts of problems. If your thermostats are set incorrectly, you’re upstairs may often be blazing hot while your downstairs is freezing cold. Both your heater and your air conditioner may end up running almost constantly. HVAC systems are designed to have breaks in their running time every now and then, so nonstop running can result in excessive wear and tear on your system. You can also end up wasting energy and paying too much for your energy bills. Fortunately, all these issues can be fixed with a few simple thermostat setting tricks.
How to Set the Thermostat for Each Level of Your Home
When setting a thermostat in a multi-story home, you need to think about whether you are going to be running your air conditioner or your heater. Then you need to take into account your desired temperature setting for your home. The general rule of thumb for a two-story home is that you should set each thermostat two degrees Fahrenheit apart from the other.
During the summer, when your AC is running, set the upper floor at the temperature you actually want in your home. Then set each floor underneath that to two degrees warmer. This gives the upstairs rooms a little help since the air up there is hotter. The extra cold air from upstairs will naturally settle downwards, so your lower air conditioner does not need to work as hard to maintain a comfortable temperature. This will help solve the problem of a chilly downstairs and hot upstairs in the summer.
During the winter, you can reverse this process. Start by setting your thermostat downstairs to your desired temperature. Then set the upstairs thermostat to a two-degree cooler setting. The extra heat downstairs will combat the cold that settles on the lower levels. Having a slightly cooler setting upstairs will not make it uncomfortably cold, since you will have rising heat to help keep the area warm.
The process is the same for homes with three or more stories. However, instead of a two-degree gap, you just need to do a one-degree gap. For example, in the summer for a three-story home, you might set your upper floor to 74, then your middle floor to 73, and your lower floor to 72. To find thermostat settings for a multi-story home with a finished basement, ignore the basement when calculating temperatures. Just set it to something comfortable, and count the ground floor as your lowest level to calculate temperatures for other floors.
Finding the Most Energy Efficient Settings
When looking for the best settings for your thermostats, the balance between your floors is only one of the factors you need to consider. Many homeowners also want to find thermostat settings that help them save energy and money. According to The U.S. Department of Energy, the most efficient settings are 78 degrees in the summer and 68 degrees in the winter. This keeps your indoor temperatures at safe and comfortable levels while using as little energy as possible.
For a two-story home, this will translate to 78 degrees upstairs and 80 degrees downstairs in the summer. During winter, you can go with 66 degrees upstairs and 68 degrees downstairs. In three-story homes, the most energy-efficient settings in summer are 78 on the upper floor, 79 on the middle floor, and 80 on the lower floor. For winter, set your thermostat to 66 degrees on the upper floor, 67 on the middle, and 68 on the lower.
If you do not use your upper story during the day or your lower story at night, you might be tempted to set the thermostat to even more extreme levels. However, cranking your thermostat way up in the summer or way down in the winter can end up causing problems. Your upstairs and downstairs levels are still affected by each other’s temperatures. If the HVAC is never running on one of these floors, it may run extra long on another floor to compensate. This can end up costing just as much money and put excessive wear on your system. You can bump the difference between floors to a four to six-degree difference, but avoid shutting off one floor’s thermostat altogether.
Syncing Thermostat Settings With Programmable Thermostats
Lately, many people have switched to programmable thermostats. These devices promise energy savings because they can automatically switch your thermostat to more energy-efficient settings when you are sleeping or away from home. You can still get energy savings if you have a multi-story home. However, for maximum efficiency, you need to actually program the thermostat instead of just going with its default settings.
For most brands of zoned thermostats, you can sync them together when you install them. However, they will not always move up and down at the same exact time. Instead, each thermostat will try to create the most energy-efficient schedule for its zone. Whether or not this is the most efficient option will depend on your individual activities. Generally, as long as the thermostats are within a few degrees of each other, you are not putting excess strain on either part of your HVAC system. If your thermostats try to entirely diverge from each other though, you may want to tinker with the settings. Depending on the type of programmable thermostat you have, you may be able to pair them with each other, or you may need to adjust each schedule individually.
At Bardi Heating, Cooling & Plumbing in Atlanta, GA, we can help design and install an HVAC system that addresses the unique needs of multi-story homes. Our knowledgeable team can also assist with HVAC repairs, HVAC replacement, and plumbing services. Schedule a service call for your Atlanta home by giving us a call today.