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What to Know about HVAC System Sizing

Tech-quote-paper-handMany people do not realize how much goes into installing an air conditioning or heating system. They may think that any handyperson could install an air conditioner or a furnace as long as they had instructions and a good tool kit. But there are many good reasons it’s necessary to have experienced HVAC installers on the job instead.

Heating, ventilation, and air conditioning contractors go through a lot of thorough training to ensure that a heating system is installed safely and securely. That doesn’t just mean following instructions. It means taking pains to ensure the system is properly sized as well, and those calculations can be more difficult than you think.

How Sizing Is Determined

Many companies provide free estimates for heating installations, but they require a visit to your home before telling you the price. You might wonder why this is—and it may seem as though it has to do with money. But this is because technicians cannot determine the proper size of system for your home over the phone, even if you read off the stats on your old heater or air conditioner.

Too often, amateur “technicians” choose the wrong size of HVAC equipment for a home. Oversized or undersized, this can lead to many problems. And the size of the equipment you are replacing may not have been correct either. Technicians check the size of your home and other factors to determine which is the right fit.

The Problem with Small Systems

Heating and air conditioning systems that are too small for a home run into some obvious problems. It’s difficult for a smaller heater to heat a large home, as you may expect. Still, some people purchase smaller air conditioners and heaters in an attempt to save money.

This likely will not turn out well. A smaller air conditioner or heater must run nonstop in an attempt to reach the thermostat setting. You pay to run the system all day and night (or manually shut it off before it completes the job). Either way, the components of the system wear down quickly, and you may have to replace it soon.

The Problem with Larger Systems

The problem with a larger system is that it may short cycle. A properly-sized air conditioner or furnace is meant to run in full cycles, as specified in manufacturing. Constantly turning off and turning on again can be damaging to a system, but that’s exactly what a larger furnace or air conditioner will do. The components wear out from this starting and stopping, and you may have surprisingly high bills.

Which Size Is Right for Your Home?

While you can choose from different efficiency ratings and special features, there is only one size of furnace or central air conditioner that is the right fit for your home. Measured in tons, the size does not refer to the weight of the system, but rather how many BTUs (British Thermal Units) of heat per hour it can move. There’s no simple formula to get this number, as it depends on a number of factors.

  • The size of the home.
  • The number of people and bedrooms.
  • Your climate.
  • Whether the home is in a shady area.
  • Whether the home has a lot of windows.

…and more. That’s why you should call in qualified installers for your new HVAC system!

For HVAC in Schaumburg, IL, trust the pros at Elm Heating & Cooling, Inc.

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