It is only common sense to turn something off when we are not using it. During our morning routine, most of us will make sure that we have turned off all the lights, the faucets, and any electronic devices that will not be needed while we are gone for the day. By doing so, we save ourselves from spending money on wasted utilities.
Does the same hold true of shutting your a/c system off during the day? Well, the short answer is that it MAY save you money if you shut the unit off or it could end up costing you A LOT more money. Is it worth it? Consider the following information before making that decision.
Theory vs. Applied Reality
The notion is that it would take much more energy out of the system to run continuously for several hours as it brings temperatures back down then just letting the system cycle on and off normally.
The reality shows this theory to be incorrect, however. Some tests indicate that keeping the unit running while you are gone may use 300% more energy than turning it off while you are gone.
However, that doesn’t actually mean that you’d be saving money. Most electrical companies charge you more money to run between 3 and 7 PM. Therefore, if you come home at 5 and run the unit continuously for two or three hours, you’ll probably end up paying more for your electricity after all.
There would be an energy savings, though. The basic scientific thought is that when your a/c unit cools your home, heat transfer becomes inevitable as the outside environment seeks to bring the indoor temperature to equilibrium. This causes your unit to cycle back on frequently. Your home becomes a sort of magnet, attracting warm air from outside.
Therefore, your unit cycles on and off more than it would need to in order to bring your home down from 90 degrees back down to the 72 degrees or so that you have the thermostat set for by running constantly.
Is It a Good Idea?
The short answer is no, it is not a good idea to shut your unit off during the day. While it may save money to keep your unit off like this it creates numerous inconveniences, which will hinder your experience and the health of your home.
First, and perhaps most obviously, your home will be extremely hot and uncomfortable when you get home. This is not like your car a/c unit. It’s going to take much more than 10 minutes for the inside of your home to cool down. In fact, during a summer evening, it could take several hours for your home to drop to the desired temperature.
Second, even if the a/c unit pulls your home down to a reasonable temperature you may not feel quite that comfortable due to the humidity in the room. Here in Georgia humidity is a real concern, and your home’s prolonged exposure to humidity can create a variety of issues that would be of concern to a homeowner.
By allowing your home to become overly humid you create an environment that hinders the performance of computer systems, damages oil paintings, and puts your home at risk for growing mold. This is especially the concern when you are away from the property for a day or more.
Finally, A/C units are designed to cycle on and off. The system is not designed for it to be shut off during the day and then expected to catch up at night. There are many pieces of equipment within your system that would not appreciate this type of cycling. Your compressor, for instance, could become severely overheated. This will lead to system failure, and replacing a compressor can be very costly.
If shutting off your system were to create any of these problems, you would lose all the financial benefits you gained by running the system less frequently.
What Should I Do?
Saving money is important, but so is making sure that your home is being taken care of properly. To make sure that you’re taking care of your home and wallet, the best solution is to use a thermostat that can accommodate your schedule.
Both smart thermostats and programmable thermostats would fall into this category. Programmable thermostats allow you to set the unit to maintain a higher temperature when you do not expect to be home. Then, based on the schedule you give it, the thermostat can kick on the unit close to the time you anticipate being home.
Smart thermostats work by using you and your family’s phone locations to determine when you are not home. You can also set it to away when you have to leave unexpectedly by means of your phone or on the thermostat itself. The advantage of this is that if your schedule changes, your thermostat will be ready to accommodate those changes effortlessly.
Though it may be cheaper to leave the system off while no one is home, it is not guaranteed and you may end up spending way more money in actuality. You’ll also need to be careful with shutting the unit off because you could damage your home and electronic devices in your home. Instead, allowing your home to be adjusted by a smart or programmable thermostat provides financial benefits to you, while also providing a healthy environment for your home and electronic devices.
Are you interested in installing a thermostat that can help you to save money on your electrical bill?