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How to choose the right size HVAC system


Keeping your family cool and comfortable during summer in Florida typically involves installing a central air conditioning system. Just how large the AC system should be can be a mystery for people who have never had a system installed before.

What some homeowners do not know is that the biggest equipment is not always the best option. In an era where people supersize their restaurant meals and want the biggest of everything, it's no wonder that some would want to install the largest available AC equipment available on the market today. However, to get maximum comfort as well as the lowest total cost of ownership of your HVAC system, it's imperative that you select the appropriate size.

Determining the proper size is a job for heating, ventilation and air conditioning professionals. You'll want to work with expertly trained technicians who have plenty of experience helping individuals in Florida match an HVAC system with their homes.

Basics of HVAC Sizing

Even though it's best to arrange for knowledgeable technicians to size your home for an HVAC system, it's a good idea to become acquainted with what is involved before you make an appointment for installation.

A technician needs to take four basic steps when sizing your home's HVAC system, according to the "Strategy Guideline: HVAC Equipment Sizing" report from the U.S. Department of Energy's Energy Efficiency & Renewable Energy Building Technologies Program.

First, you calculate the heating and cooling loads for the dwelling, as accurately as possible. How big is the house? How large are the rooms, and how many are there?

Then, you select your brand of cooling equipment. After then choosing what heating equipment to include, it will be time to design the ductwork (unless you are going for a ductless HVAC system, which you can consult about with the technician, of course).

Air conditioning experts speak about the size of equipment to be installed in terms of tons. This is not "tons" in the sense of a heavy weight. In the HVAC world, a ton refers to the ability of your AC system to cool 12,000 BTUs (British Thermal Unit) per hour.

Scientists use BTU to indicate how much energy is needed to cool one pound of water by one degree Fahrenheit. HVAC systems installed in Florida homes can typically range from 1-ton to 5-ton. Larger units are usually installed in commercial settings or enormous mansions.

HVAC technicians often use software to help them do a Manual-J calculation to evaluate how big the system needs to be for any given home.

If the HVAC system is too big, it will turn on, begin to cool the house very quickly, and then turn off again. Rapidly shutting the AC on and off is inefficient and a sign that the system needs to be smaller, so it can operate for its full cycle. Installing the correctly sized system means that it won't be overworked (which can make equipment wear out sooner) and you won't see skyrocketing utility bills (at least not from your ordinary HVAC usage!).

Before the weather really begins to heat up and your family starts complaining about how unbearable it is inside the house during the summer, it pays to contact HVAC professionals with experience in the greater Jacksonville, Florida area, such as the team at David Gray Heating & Air.

In order to really figure out how large the HVAC system should be requires training that you as a homeowner will want to take advantage of. Getting the right sized HVAC system means that you can rest assured that your home will be adequately cooled without overworking the AC equipment and driving up your power bills. For more information on choosing the right size HVAC system or to make an appointment for service, please contact David Gray Heating & Air today.