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Choosing the Right Size Commercial HVAC System for Your Facility

The size of commercial HVAC systems directly impacts costs, maintenance, and overall heating and cooling performance. Choosing an HVAC system that doesn’t correspond with the size and layout of your commercial building can prove inefficient and wasteful, potentially costing you much more in high electrical bills. However, sizing commercial HVAC systems to best suit your facility’s needs can lead to better results from your unit and improve efficiency. But how do you size commercial HVAC systems correctly?

Keep reading to better determine the best size commercial HVAC system for your business using these topics:

  • The importance of sizing commercial HVAC systems
  • How to size HVAC equipment
  • The advantages of adequately sized commercial HVAC systems

Why Sizing Commercial HVAC Systems Matters

Installing an incorrectly sized HVAC system can negatively affect your wallet and hinder your unit’s performance. Undersized HVAC units cannot properly keep spaces air-conditioned or pump an adequate amount of heat to warm commercial buildings. Not only is this an efficient way to achieve desired internal temperatures, often leading to hot or cold spots in large spaces, but it pushes the HVAC system to its limits by straining to do its job, causing wear and tear on its internal components and increasing energy expenditure.

Overestimating the sizing of commercial HVAC systems is no better. True, your commercial building may reach its optimal temperature with ease, but it isn’t doing so in a way that is energy efficient. Oversized units waste energy by consuming more than is required to heat or cool the space. They also cost more upfront, require additional maintenance, and increase humidity levels, leading to mold and discomfort.

Either way you look at it, selecting the wrong size commercial HVAC system costs you money, wastes energy, and fails to provide the best available comfort.

Sizing Commercial HVAC Systems

HVAC sizes are measured in “tons” or “tonnage,” which refer to a system’s Btu (British Thermal Units). Btus equates to the amount of energy needed to raise or lower the temperature of one pound of water by one degree Fahrenheit. Depending on the size of a building, most commercial HVAC systems vary between 2 to 30 tons, with one tonnage capable of removing approximately 12,000 Btu.

HVAC Sizing Considerations

Knowing how to calculate estimated sizing for commercial HVAC systems can point you in the right direction, but there are other factors to consider before choosing a unit.

  • What are the current internal and external loads generated by your building?
  • What is the space being used for? (A restaurant, a retail store, an office?)
  • Does the facility have high ceilings, multiple levels, or a basement?
  • What’s the total square footage of your building?
  • Are there many rooms or large open spaces?
  • How many windows are there and how large are they?
  • Does the building use electric or gas heating?
  • How many people are expected to use the space throughout the day?
  • What material are the floors, ceiling, and walls made of?
  • How thoroughly insulated is the facility?
  • What types of electronics are being used daily, and how many?

Factoring these elements into your calculations can provide a more accurate estimate for your HVAC sizing.

Calculating an accurate estimate for your commercial HVAC sizing can be challenging, especially for those unfamiliar with general procedures. Get precise measurements by hiring a commercial HVAC professional like SAM Mechanical Services to achieve the most efficient energy expenditure and reduce costs.

New Hampshire’s Go-To Commercial Mechanical Contractor

How to Size HVAC Equipment

Knowing how to calculate tonnage for HVAC units can help you obtain accurate measurements for a new heating and cooling system. Here’s how to get started:

  1. Consider all factors and calculate the total square footage of the areas that need cooling.
  2. Take that total and divide it by 500
  3. Multiply that divided total by 12,000 (the approximate amount of Btu one tonnage can remove)
  4. Add 380 Btu for the estimated number of occupants in the facility, plus an additional 1,000 Btu for every window and 1,200 Btu for each kitchen if any are present.
  5. Divide your latest total by 12,000 to convert it into Btus.
  6. Use this calculated total to determine the correct size HVAC system.

The Benefits of Correctly Sizing Commercial HVAC Systems

  • Improved Comfort

    When HVAC systems are sized correctly and function as intended, desired room temperatures are more likely to be achieved with minimal effort. This ensures that the comfort of your customers and employees is maintained throughout the day, regardless of the temperature outside.

  • Efficient Energy Expenditure

    While undersized or oversized HVAC units can’t operate efficiently, carefully chosen equipment uses an appropriate amount of energy when heating and cooling spaces. Properly expended energy leads to reduced spending on bills and maintenance and minimizes harmful impacts on the environment.

  • Less Maintenance

    HVAC units sized for specific facilities don’t have to work as hard to circulate cool air or heat throughout a commercial building, which means they last significantly longer and require fewer repairs. This also means your unit is less likely to break down between seasonal inspections.

  • Higher Air Quality

    Bad air quality can instigate allergies and create unpleasant working conditions. However, correctly sizing commercial HVAC systems ensures that the air circulating through your ducts is of the best quality possible. This keeps humidity levels low while maintaining a consistently clean and welcoming environment.

  • Cost Savings

    Not only do you save money upfront by selecting an HVAC unit that isn’t larger than you need, but less maintenance and energy also work to secure your bottom line. Rather than spending money on avoidable hindrances, you can divert cost savings directly into your business.

Ensure an Accurately Sized Commercial HVAC System With SAM Mechanical Services

Partnering with a professional heating and cooling provider is the best way to guarantee your commercial HVAC unit is the correct size for your facility, and no company is more reliable than SAM Mechanical Services. As an experienced HVAC contractor, we’ve served a wide variety of clients in New Hampshire across multiple industries for over three decades. We like to keep our clients in the loop as much as possible, so we collaborate with them from start to finish to deliver the most efficient HVAC solutions for their commercial buildings. In doing so, we help them increase energy efficiency, save them money, and keep them comfortable no matter what.

Our trained and certified experts can give a precise estimate as to the best size commercial HVAC system for your building. If you’re happy with the results, we’ll gladly install it promptly and efficiently—and at a competitive price—so that your customers and employees can reap the benefits. If you’re interested in accurate and detailed work, give us a call. Our team is available around the clock!

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