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Air Conditioning

Where Do I Find The Tonnage of My AC Unit?

 My AC Unit

Thinking about replacing your AC unit soon? Aire Serv of Wake County in Raleigh can help you find the tonnage of your current heating and cooling system.

Where Do I Find My AC Tonnage?

Your AC tonnage can easily be found by going outside and looking on the AC unit itself. When outside, you should see a data plaque mounted to the side of the condensing unit. Look for the model number, which is a combination of numerals and letters. Within this combination, you should find an even, two digit number. Tonnage on residential HVAC units range anywhere from 18 to 60.

Once you found the even number on your unit, divide it by 12. 12 represents 12,000 Btu/hr, or one ton of cooling capacity, to get your AC unit’s tonnage.

No need to do the math; we have the numbers broken down below and their corresponding tonnage.

  • 18 = 1.5 tons
  • 24 = 2 tons
  • 30 = 2.5 tons
  • 36 = 3 tons
  • 42 = 3.5 tons
  • 48 = 4 tons
  • 60 = 5 tons

What is AC Tonnage?

Heating and air conditioning capacities are measured in British thermal units (Btu) per hour. A single Btu is equal to the heat produced by a one birthday candle.

“Tonnage” describes the cooling capacity of your air conditioner. One ton of cooling is the rate of heat transfer needed to freeze 2,000 lbs – or one ton – of water in 24 hours. This is equivalent to 12,000 Btu/hr.

Why is AC Tonnage So Important?

Bigger is always better, especially when it doesn’t cost more. But sometimes less is more, when it comes to air conditioners. Be careful of heating and cooling contractors that try and sell you the largest AC unit possible. An oversized system doesn’t necessarily mean it’s the best option for your home. Here are some issues associated with an oversized home air conditioner:

  • Increased wear and tear on the AC unit because of short cycling leads – which can result in premature replacement or increased repairs.
  • Dehumidification because of short cycling – which can leave your home cool but damp inside. Homeowners will continue to turn the thermostat down to prevent this issue and will raise their energy usage in the process.
  • Larger AC units cost are more expensive to buy and maintain, especially when a smaller air conditioning system is more compatible for your home.

The opposite effect can happen with an undersized air conditioning system. An AC unit that is too small for your home’s square footage won’t be able to stay cool on warm days.

The Importance of Sizing a New Air Conditioner

Be mindful knowing that the current tonnage of your AC unit doesn’t always guarantee your new replacement system should be the same size.

  • Have you made home improvements since your last air conditioner was installed? If so, your home may be more efficient.
  • Have you added additional square footage to your home?
  • It’s, also, probable that your current AC unit was never originally sized correctly for your home.

Call Aire Serv of Wake County for Help Sizing Your AC Unit

Our air conditioning professionals in Cary can walk you through the AC-buying process. We will help you choose the proper size HVAC system for your home and ensure it’s a high-quality brand with a cost-effective efficiency rating. Our licensed experts are, also, professionally trained to install the unit you choose on a day and time that is convenient for you.

Call Aire Serv of Wake County today for a free estimate on a replacement AC system for your home.

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At Aire Serv, we strive to keep the air in which we live and breathe comfortable and clean, so people live healthier, happier lives. Since 1992, our brand has stood for excellence and putting customers first. When you see the name Aire Serv, you can expect quality services and customer attention. With over 200 locations across the United States and Canada, Aire Serv is a trusted name in the field of heating and air conditioning installation, maintenance, and repair.

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