Commercial HVAC systems seem to get all the love with engineers devoting months to designing them to be just right. Many homeowners don’t have this luxury and their systems are often sized based on square footage. And while these rules of thumb are quick and easy, the long term effect of poorly sized equipment can be costly and stressful.

Heating

It may seem obvious that if your furnace is undersized, you just won’t get the heating you need. You’ll shiver winter after winter while you wait for the temperature to go up. But that’s not the only indicator. You may find some parts of your home get warm while others are cold. One typical reason is that the airflow isn’t properly balanced. Another possibility is an undersized furnace that simply can’t heat your entire house.

More often than not, though, the problem is that your unit might be oversized. Unfortunately, this means a higher initial cost and potentially higher energy consumption to power a larger fan. If you have a single stage furnace, you might find it cycling on and off more frequently. Your home’s temperature will fluctuate and your furnace will experience more wear. Modulating furnaces aren’t prone to this problem but they will run at a less than optimum efficiency, consuming more fuel than if properly sized.

Poorly designed cooling

In northern climates, air conditioners are sometimes considered less important. While heating is more critical for severe winters, cooling systems are vital for both temperature and humidity control in the summer. An undersized air conditioner will struggle to cool your home and run longer, drawing more power. It will also take a long time to bring the temperature and humidity down, leaving you at risk for all the issues associated with high humidity.

Similar to furnaces, some air conditioners may be oversized, especially in hotter climates where air conditioning is critical for extreme temperatures in the summer. The problem is that oversizing your air conditioner can increase wear as the compressor cycles on and off for single stage cooling systems. It can also lower humidity too much, leaving your home dry and uncomfortable. Added to that is the higher initial cost and energy use for a unit that is bigger than it needs to be.

There’s no question that much thought needs to go into choosing the right equipment for your home. If your HVAC system isn’t performing despite proper repair and replacement, give us a call and we can assess the design to help you deal with those issues.