AC On or Off during the day? - Advanced Air & Heat of Florida LLC AC On or Off during the day? - Advanced Air & Heat of Florida LLC

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Does turning your Air Conditioner off during the day save you money

The largest portion of your monthly energy bill is probably your AC usage. So naturally you want to know how to keep that electric bill down by lowering your air conditioner use. In Florida, that seems almost impossible during the hot summer months.

The most common HVAC question our AC techs get is “Should I keep my air conditioner on or off while I’m at work?”

Some say you should keep your A/C off while you’re at work because running the air all day is a huge waste of energy (and money).

The other thinking is keeping the air conditioner off all day means it has to work twice as hard in the evening to cool down your hot house. After all, temperatures inside can reach the high 90s during the summer heat peak. Meaning, when you finally turn the air conditioner on at night, it will have to cool your entire house down by 20 degrees instead of maintaining a cool temperature all day.

The question remains…A/C on or off during the day?

The truth is, both answers are correct. The best thing to do is keep your air conditioner on, set to a high temperature during the day.**

The closer the temperature is inside to the temperature outside, the less your HVAC system will have to work. However, leaving the air conditioner off all day will make the temperature inside the same or higher than outside, but it will also make your HVAC system work twice as hard to cool off your home later on. Plus, no one wants to come home to a hot house. Especially when it’s 95 degrees outside.

Setting your thermostat to a high temperature (mid 80s) will ensure your home doesn’t get too hot during the day, but your air conditioner won’t be running all day either. Keeping the AC off all day will make the temp inside rise sky high, so waiting until evening to turn on your air condtioner will push your HVAC system to its limit. And then it will break, and you will need to call your local AC company. (That’s Advanced Air & Heat)

Another HVAC tip: close the curtains. You will trap the cool air from overnight inside and require your cooling system to work less to maintain the high midday temperature.

What about keeping the AC off and the fans on?

Leaving the fan on will only move the hot air around and burn electricity. Fans do not create cool air; they only move air around. If your home is hot, leaving your fan on will only circulate warm air throughout the room.

An even better solution is to install a programmable thermostat. Programmable thermostats seem expensive at first, but they are more than worth the investment. A programmable thermostat allows you to keep your air conditioner off during completely unused hours of the day, and start to cool off your home an hour before you come home from work. This way, your A/C usage is optimally limited during the day. The initial $100 cost of a SMART thermostat can save you over 10% on your electric bill over the year. That can mean savings of about $1,000. Not to mention all of the fossil fuel conservation you will be doing to help the environment. Find out more about programmable thermostats here.

In summary, keep your AC turned up to about 85 during the day. And save up for a SMART thermostat to save you the most money in the long run.

**Suggestion is only true if you are out of the house for more than 4-5 hours.


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