How To Size an HVAC System: What Do Pros Do?

Do you know how to size an HVAC system? Is this an important skill for you to master before agreeing to install a specific-sized heating and cooling system on your property? Well, an improperly sized HVAC unit could cause numerous issues, including the following:

  • Inefficiency
  • A shorter useful life
  • Poor energy consumption and more 

Below, the BVS home experts discuss some of the ways in which the right size air conditioner or heating system could benefit residents and business owners who want premium HVAC services in Richmond, TX.

Why Your Home’s HVAC System’s Size Is Important

As one of Richmond’s most trusted heating and cooling companies, BVS has served this community for over 40 years. In that time, we have seen how choosing the perfect size HVAC system can make all the difference to how it performs in your unique location. Many people believe the bigger the HVAC unit, the better its performance, but size does not equal efficiency.

For example, an undersized HVAC system will run constantly and have trouble adequality cooling the entire home. The nonstop operation will increase your monthly energy costs. It will also shorten the lifespan of the unit.

Conversely, an oversized HVAC system provides inconsistent indoor temperatures. It quickly creates hot and cold spots throughout your building, cycling on and off too frequently to maintain any balance in efficiency. This increases the energy bills while making the larger units more prone to serious damage.

So, how do we choose the perfect size HVAC system? We use the square footage of your home or business as a helpful starting point. A large house requires a bigger heating, ventilation, and air conditioning unit compared to a small apartment.

How To Size an HVAC System Correctly

If you want to optimize the energy efficiency of your heater in winter or the air conditioner in summer, the system size needs to correspond perfectly to your home’s size and setup. That’s the first secret to how to size an HVAC system. The next step is to determine which type of heating and cooling unit your home has or ask a professional team like ours to help with this task.

A typical Richmond home would bring the following considerations when deciding on the HVAC system type you need:

  • Does your home have a forced-air heating system? A five-ton HVAC unit might be best.
  • Residences utilizing gas heat typically require a heat pump that provides heating and cooling (the size depends on your preferred heating system).
  • Average-sized homes using electric heat often need a three-ton unit.
  • Residences without forced air heating systems must find their heater’s BTUs (British Thermal Units) to determine the correct size.
  • Most outdoor HVAC units include a sticker to inform homeowners about the size and type of air conditioner so that they know what they need for replacement purposes.

If your home doesn’t have an air conditioner, consider which rooms need cooling to determine its size. It’s best to contact a professional like BVC for an assessment to determine which size and type of air conditioner might suit your needs and location. 

Determining the Best BTU Rating for Your Home

A home’s size will determine how many BTUs the HVAC system should have to cool or heat it effectively. In general, an HVAC system’s BTUs calculate the unit’s requirements for heating or cooling one pound of water by one degree.

The residence’s square footage solely determines an HVAC system’s ideal BTU rating. So, a good starting point is to calculate your home’s total square footage, including its ceilings and floors. Then, use the chart below for an idea of how to size an HVAC system using an ideal BTU rating:

  • 100-150 sq. ft – 5,000 BTUs
  • 150-250 sq. ft – 6,000 BTUs
  • 250-300 sq. ft – 7,000 BTUs
  • 300-350 sq. ft – 8,000 BTUs
  • 350-400 sq. ft – 9,000 BTUs
  • 400-450 sq. ft – 10,000 BTUs
  • 450-500 sq. ft – 12,000 BTUs
  • 500-700 sq. ft – 14,000 BTUs
  • 700-1,000 sq. ft – 18,000 BTUs
  • 1,000-1,200 sq. ft – 21,000 BTUs
  • 1,200-1,400 sq. ft – 23,000 BTUs
  • 1,400-1,500 sq. ft – 24,000 BTUs
  • 1,500-2,000 sq. ft – 30,000 BTUs
  • 2,000-2,500 sq. ft – 34,000 BTUs

There are also very helpful online tools to help you decide the best-sized air conditioner and heater for your home in Texas.

The “Manual J” Method

Many heating and cooling specialists will use the Manual J calculation method to decide the best HVAC system size for a home or office building. It requires the following information:

  • The home’s total cubic feet
  • The attic insulation type
  • The region’s climate classification

First, the technician measures the outdoor temperature and the home’s average indoor temperature during the winter. They also examine the attic’s insulation and your residence’s climate zone. The HVAC technician will then submit this information into the Manual J calculation chart to determine your property’s perfect size HVAC system.

It might also be an idea to contact your Texas utility company to perform an energy audit. The process might include a Manual J calculation. If not, you can always find a reliable HVAC distributor to conduct the calculations on their behalf.

It is easiest to leave the Manual J analysis to a professional technician or auditor. Extensive experience in conducting energy audits is helpful for getting around the many curve balls that different homes present, and they will be able to gather the most accurate information. The smallest miscalculation jeopardizes the decision, and you will likely buy the wrong size HVAC unit.

Contact BCS Home Experts for First-Class Heating and Cooling Services in Richmond, TX

Would you like to explore the options for a new HVAC system for your home in Texas? Whether you need to replace your HVAC system or learn efficient tips to improve indoor air quality, the BVS home experts are here to help.

Call BVS Home Services at (281) 916-8699 today for more tips on how to size an HVAC system or an estimate on installation, repairs, and maintenance in Texas.

Author Bio:

Ronald Via

Ronald is one of the key contributors to BVS Home Experts, a family-owned and operated full-service air conditioning and heating company serving the Katy and West Houston areas. With a deep understanding of air conditioning and heating concerns, Ronald brings a wealth of knowledge to our readers.

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