SPRINGFIELD, Mass. (WWLP) – It’s day one of the expected heat wave, and you’ll probably have your AC running all day.

But when the temperature outside increases, your AC unit’s efficiency can dramatically drop. There are many different brands, sizes, and types of air conditioning units on the market, but making sure it is doing what it is intended to do is the most important part.

The hottest time of the day is between noon and 4 p.m. This is when the sun is at its highest and more heat is arriving than leaving. Make sure you are closing your blinds and windows for this time period to avoid heating the inside of your house. It’s important to properly seal your house to keep the cool air from your AC inside your house. Using your oven or dryer during the cooler hours of the day will ensure that you’re not overworking your AC either.

David Lunden, an assistant manager at Manny’s Appliances in Westfield said, “The most important thing is we need to get a sense of how large or how small of an area you are trying to cool. Over-sizing is not any better for an AC than under-sizing. If you under-size then the room doesn’t get cool and if you over-size then the room cools down too quickly and then you don’t get proper humidity control.”

Many AC units these days have a programmable thermostat, which can help you save energy while keeping your home cool. Setting the AC to a certain temperature for the afternoon hours compared to the overnight hours will make sure the temperature within your room or home is staying constant and comfortable.

This heat is going to be sticking around unfortunately, but not forever.