How to Size an HVAC System: A Step-by-Step Guide

If you want to keep your property’s climate comfortable, installing a heating, ventilation, and air conditioning system can be a good idea. However, this isn’t just about choosing the biggest or newest one. You need to size your HVAC unit properly to ensure it’s efficient.

An inaccurately sized HVAC system can cause several problems, including inconsistent and uncomfortable temperatures, annoying noises, potential mold growth due to insufficient moisture removal, and high energy consumption, which can create unhealthy environments and increase your bills each month.

Fortunately, you can avoid these potential issues, make sure your HVAC unit works efficiently, and even save money by properly sizing your system. Do you want to learn how to do it? Below is everything you need to know!

Steps to Properly Size Your HVAC System

Do you need to regulate your property’s temperature? Whether you’re installing a residential or commercial HVAC system, you should make sure it’s properly sized. Complete the following steps to do so!

Calculate the Square Footage

Not every HVAC system will be suitable for any space. It must have the appropriate size to keep the chosen area at a comfortable temperature. 

So, the first step you should complete is to calculate the square footage of the area where the equipment will be installed. 

If you don’t have this number written down, you can measure this space yourself using tape to determine the length and width. Then, multiply both together to get the square footage.

Determine the Base BTU

Once you calculate the area’s square footage, you must determine how many BTUs are required for that space.

BTU stands for “British Thermal Unit,” which measures the amount of energy needed for heating and cooling. As such, this calculation will help you determine an HVAC system’s capacity.

Since cooling a space takes around 25 BTUs per square foot, the formula to determine the right HVAC system’s capacity is the area’s square footage times that number.

That means you need to multiply the area’s square footage by 25, and the result will be the base BUT measurement.

Consider Your Ceilings

If your property’s ceilings are over 8 feet, you may need an HVAC unit with greater capacity. In this case, it’s recommended to multiply the BTU amount by 25% or 1.25.

Convert Those Measurements to “Tons” for Your Central Air Conditioner

The next step is complicated, but it’s so important. You’ll have to calculate the required tonnage for your air conditioner (AC).

In a central air conditioning system, “tonnage” describes how much heat the cooling unit can remove from the air in just one hour.

As mentioned, heat is measured in British Thermal Units or “BTUs.” Each ton is equivalent to 12,000 BTUs of air per hour.

If you want to determine an area’s tonnage, you must multiply the square footage by 30 and then divide it by 12,000.

It’s important to understand that these calculations may vary depending on the number of windows and doors in the area needing temperature regulation.

Consider Manual J Calculation

As you can see, the former calculations are basic and don’t consider other important details, such as:

  • The number of people who use space
  • The area’s climate
  • The amount or type of wall insulation
  • The placement of lighting
  • The number of doors in that space
  • The number of north- and south-facing windows

Manual J calculations are more intricate but can help you determine the right HVAC unit size for an area based on how much heating and cooling it demands. However, this requires more details about the property and location.

For example, it’s recommended to add more BTUs to the calculations per window, door, or person as follows:

  • 100 BTUs per person occupying the area
  • Between 400 and 1,000 BTUs per window
  • 1,000 BTUs per door

These recommendations are for spaces with ceilings below 8 feet, which means you may need other details to determine the number of BTUs your air conditioning system requires in other cases.

Manual J calculations are the nationally recognized standard for defining the right HVAC size and load. As they’re too complex, these measurements are often determined by professionals with extensive experience in heating and cooling system installation.

By using professional HVAC installation services, you can make sure your property’s temperature is consistent and comfortable while ensuring energy efficiency, indoor air quality, adequate moisture removal, and optimal performance to protect your investment.

Is It Necessary to Hire Professionals to Properly Size HVAC Units?

As mentioned above, HVAC systems must be of the correct size. Otherwise, they may cause several issues.

If your HVAC unit is too large, it won’t operate at its maximum efficiency, can wear out faster, and accumulate moisture. Contrastingly, if it’s too small, this system won’t be able to regulate the temperature throughout the entire space.

Whether you’re installing air conditioning systems for a commercial building or estimating the correct HVAC unit size based on your house’s square footage, you can try doing these calculations yourself. However, this is more complex than it seems. Therefore, the best thing you can do is contact experts.

Professionals have the knowledge needed to calculate how many BTUs your HVAC system should provide or the number of tons air conditioners should have based on your building or home square footage. 

Additionally, they’ll consider other key aspects to choose the best units and ensure your spaces have the ideal temperature throughout the day. Pure Eco Inc. Long Beach HVAC company can help you with HVAC units of any size.

Pure Eco Inc.: A Reputable Long Beach HVAC Company

Do you want to find a reputable HVAC company to determine the correct air conditioner size, install a new system, or perform maintenance on your existing one? If you’re in Long Beach, Pure Eco Inc. is near you!

This trusted company offers comprehensive services to help Long Beach property owners optimize their spaces’ comfort, ensure air purification and quality, and even reduce energy costs!

Whether you need to install water heaters and heat pumps to make sure your property stays cozy in the winter or a properly sized air conditioner to cool key areas during the summer, these professionals can give you a hand.

Working with experts is the best way to determine an HVAC system’s size and capacity. Get in touch with a reputable team before installing yours!

 

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