The size of the A/C unit is one factor that many homeowners fail to consider, and while an HVAC professional can help you choose the best unit based on the size of your home, it’s important to understand why an A/C unit’s size is important. In short, if an air conditioning system is not properly selected for the square footage of the home, problems can quickly arise. If a unit is too small, the home may prove difficult to cool, leaving some areas of the home overly warm even though the A/C unit is working overtime to try and cool it. If a unit is too large, the system may cycle between on and off too frequently, wasting energy and costing you money.