“What size HVAC unit do I need?” is a common question we’ve often been asked.
If you’re thinking of replacing your air conditioner or HVAC unit, one of the most important considerations is size.
Size matters. Proper system sizing is crucial for choosing the right HVAC unit for the square footage of your house.
Mess up the A/C size, and you could end up with a unit that doesn’t keep you cool and comfy — and could mean more wasted money for an air conditioner or furnace unit that doesn’t fit your needs.
Streamline Heating and Air here: we understand the struggle of finding the right A/C and HVAC unit for your needs. The good news is that we have your back.
We created this article that explores proper air conditioner sizing and what to do to determine the right air conditioning unit for your home. Join us as we explore key tips to help you find the right A/C unit for you, your home, and your wallet.
The 5 steps for determining the right A/C unit for your home
| 1. Choose an HVAC system that fits your home’s dimensions. 2. Review SEER2 and BTUh ratings for your preferred A/C system. 3. Pick the right air conditioner unit size for your home. 4. Schedule an energy audit of your home. 5. Pick your preferred A/C installation team to install your new unit. |
What happens when an air conditioner is too large?
A system that’s larger than the home’s capacity (and needs) can be beneficial in that the system reaches desired indoor temperatures fast. But, the downside is that a larger-than-needed A/C system will cycle on and off often.
An air conditioning system that cycles on and off a great deal can waste energy and cause premature wear and tear on the unit. The equipment’s lifespan can decrease and maintenance costs creep up.
What’s more, humidity can rise inside a home, making the indoor air quality uncomfortable. Plus, mildew and mold build-ups can make the indoor air unhealthy for daily living.
What happens when an air conditioner is too small?
The opposite is also true: if an air conditioner is smaller than is needed for a home, your A/C might stay on longer to keep the air cool and comfortable. A central air conditioner — one that’s smaller than a home’s heating and cooling needs — can strain an HVAC unit.
The reason is that the A/C unit shoulders a greater load on the system than is warranted for the home’s air-related needs. Finally, with higher energy costs and extra labor, an undersized HVAC system can cause uneven heating and cooling throughout a home.
All the more reason to find an HVAC system that’s right for your home. We’ll explore how in the next sections.
5 Steps to choosing the right A/C system
To figure out which air conditioner system and HVAC unit you should buy for your home, you’ll want to find an A/C system that fits your home’s size, is top-quality, and is built with the latest technology.
Below, we’ve listed our 5-step process for choosing the right size air conditioner for your needs.
1. Determine the HVAC system for your home and its dimensions
When choosing an A/C system that meets your needs, you’ll have your choice between three main types of air conditioning systems:
- Split system air conditioners
- Ductless systems
- Packaged units
Split system air conditioners involve an outdoor air conditioner or heat pump and an indoor furnace or air handler combination. The indoor and outdoor parts help keep the temperature and humidity within your home under control. Split-system air conditioners are an efficient, budget-friendly cooling option that produces little noise.
Ductless systems — often called mini-split systems — consist of single outdoor units that connect to one or more indoor units that help disseminate air throughout a home. A ductless system doesn’t need to be modified a great deal to fit your space.
As such, ductless systems are often used for single rooms and smaller spaces. They work in tandem with multiple indoor units in homes and environments where different temperatures are preferred in different parts of the home.
Finally, we have packaged units. Packaged units are single outdoor units that incorporate all the mechanical components of an air conditioning system in one unit.
A packaged unit connects to a home’s ductwork and thereby distributes heating and cooled air straight into a house. These units are desirable for homes with minimal square footage and interior space.
Packaged units are also ideal for homes that don’t have attics or basements.
2. Review A/C ratings for the system you need
Before choosing a unit, you’ll want to make sure you review air conditioning ratings. HVAC professionals often assign a rating to an air conditioner based on two rating scales. The rating scales are called:
- Seasonal energy efficiency ratio (SEER2) ratings
- Tonnage or British Thermal Units per hour (BTUh) ratings
These ratings help determine the efficiency and cooling capacity of the system you want to install and buy. Understanding SEER2 and BTUh ratings can help you make a more informed purchase when finding the right air conditioner for your home.
Let’s break these ratings down.
A detailed dive into A/C unit ratings
SEER2 ratings are a calculation used to measure the energy efficiency of a specific HVAC system. You can calculate the SEER2 rating of a unit by dividing its cooling output in an average cooling season by the total amount of energy used.
The final number tells you the maximum efficiency of the unit. As such, systems with higher SEER2 ratios are more efficient.
The most common systems have a rating between 14 and 16 SEER2. More expensive, high-efficiency systems clock in at 22 SEER2.
BTUh and tonnage ratings calculate the amount of energy the air conditioning or HVAC system takes to remove heat from a home in one hour. Depending on the manufacturer, some use BTUh ratings and others use tonnage ratings.
For context, here’s a little math for you.
A 1-ton rating is equal to a 12,000 BTUh rating. Ratings are measured in increments of 0.5-ton points creating a 1.5, 2, 2.5, 3, and so-on rating.
“So, what do these ratings have to do with choosing the right size air conditioner?” You might wonder. Choosing the right system depends on the square footage of your home and the climate you live in.
The larger the home you live in, the higher the rating you’ll need for your home. Understanding the BTUh and tonnage rating will give you a better understanding of finding the right system size and specifications for your needs, as you’ll understand which units are most efficient for your home’s unique needs.
3. Choose the A/C unit size for your home
“What size air conditioner is best for me, now that I know the ratings of each unit?” Our clients often ask.
Beyond ratings, other factors play a role in choosing a unit that fits your home’s capacity needs.
To determine the BTUh number of your home, multiply your home’s total square footage by 20. To find the tonnage rating of your home, divide the BTUh number by 12,000.
This calculation will give you a rough estimate of the size of the A/C unit that will best fit your home.
Nonetheless, to find the best A/C unit for your home, you’ll want to talk to an A/C dealer, an A/C installation team, or a professional energy audit team to ensure you’re getting the most bang for your buck on your new A/C unit.
4. Schedule an energy audit and Manual J calculation
Speaking of energy audits, the information you can glean from a professional energy audit can help you better maintain comfort in your home and ensure a long-lasting A/C system.
When you contract out professionals to conduct an energy audit, they’ll use a special calculation called a Manual J calculation. This calculation is the standard BTUh assessment used across the industry to determine the energy utility of a new HVAC system.
The Manual J calculation is one of the most accurate measurements to determine HVAC capacity.
This calculation takes a number of factors into account to help determine the energy output of an HVAC system. Some of those factors include:
- The climate where the unit will be
- Ductwork involved
- The home’s (and HVAC unit’s) exposure to sun or shade
- Whether your home is well-insulated
- The number of individuals occupying the space
- Any appliances that might generate heat in the home
With the increasing emphasis on energy efficiency and sustainability across many industries — in addition to regulatory mandates to ensure more sustainable HVAC systems (Dataintelo.com, 2024) — homeowners can find an eco-friendly A/C unit that meets their needs and delivers top-quality performance.
5. Schedule an A/C installation with a reputable A/C installation team
After you’ve met with an HVAC dealer or energy auditor to determine the right size and make of your new A/C system, all you need to do is install your new A/C system. To do so, you’ll want to reach out to an expert team that has done business for decades.
For example, check on the HVAC company’s certifications and track record of success via Google Reviews and other websites that review trade professionals and their businesses. Once you’ve chosen a company to install your new HVAC unit, sit back, relax, and enjoy.
It’s time to enjoy the cool air in your home. Pat yourself on the back for finding the right air conditioner for your needs — a job well done.
HVAC tip from Streamline Heating and Air
Since air conditioning equipment regulations have taken effect recently, the cost of an A/C unit might increase soon.
If you’ve been considering a new HVAC system, ask your local A/C repair team about end-of-the-year specials and 0% APR financing options. Find more helpful HVAC and A/C tips on our Facebook page here!
Book your A/C and HVAC unit installation today!
If you’re looking for the right air conditioner size for your home — and you happen to live in the Sarasota, Florida region — give our Straightforward Professionals a call. Our friendly and knowledgeable team will help you determine the right HVAC system for your needs and walk you through the latest trends in heating and cooling systems.
Plus, we offer large and small systems, and we can even construct new HVAC systems for you. Whatever your needs may be, let our team of tradesmen provide simplified solutions for all your heating and cooling needs.
Contact us today for a complimentary, zero-risk quote on finding the right size unit for your next air conditioning project.
