How Does Your Home's Climate And Location Affect Your AC Design?

Posted on: 8 November 2022

There are very few places in the United States where you can design a new home without installing a whole-house air conditioning system. Typical homes use split-system central air conditioners with an indoor air handler and outdoor condenser unit, although package systems may be common in some areas. Most homes also pair these systems with a forced-air heating unit.

While these aspects of air conditioning design are typical nearly anywhere in the country, the specifics can vary substantially. Climate is often one of the most significant factors for air conditioning design, and it can impact your new system in surprising ways. Keep reading for three climate and location factors directly impacting your AC installation.

1. Climate Zone

Many parts of the country require a 'manual J' calculation to meet code requirements for new HVAC installs. This complex calculation accounts for numerous factors influencing your home's cooling load, ultimately providing an exact sizing fit for your air conditioning system. While this calculation will mostly look at your home's characteristics, the base cooling load depends heavily on your geographic location.

Your climate cooling zone will determine your basic tonnage requirements for keeping your home cool throughout the summer. The final manual J calculation will modify this number up or down based on insulation, the number of windows, and numerous other small details. Still, the climate in your area always acts as a basic starting point.

2. Orientation

Surprisingly, even your home's orientation matters when calculating your cooling needs. The facing of your home determines how much solar energy it receives throughout the day. You've probably heard that you should place house plants in south-facing windows. This common gardening advice comes from the fact that the southern part of your home usually receives the most sunlight throughout the day.

As a result, a home with a northern orientation (or with more north-facing windows) will usually have a lower cooling load than a home with primarily south-facing windows. While the direction of your windows may seem like a minor detail, it can have a huge impact on your AC design, potentially forcing you to buy a larger system to keep up with the heavier cooling load.

3. Humidity

Your air conditioner both cools and dehumidifies, with this latter role being surprisingly important. A humid home will tend to feel less comfortable, usually resulting in lower thermostat setpoints and more energy usage. Since air conditioning systems can only dehumidify while running, a well-sized system must cycle long enough to keep humidity at comfortable levels throughout the day.

Counterintuitively, large systems can be less effective in areas with high humidity. Since these systems will run for less time, they won't remove as much humidity from the air. As a result, humidity is a particularly crucial consideration when designing an air conditioning system for your home.

To learn more, contact an air conditioning contractor in your area.