To estimate your AC tonnage needs, multiply the number of square feet you're cooling times 25. This equals the total number of BTUs you need to adequately cool your space.
As a general rule of thumb, you'll need 1 ton of cooling capacity for every 400-600 square feet of a bedroom. A 1.5-ton AC unit is suitable for a bedroom that is up to 900 square feet, while a 2-ton AC is appropriate for a room that is up to 1200 square feet.
The square footage covered by a 3 ton AC unit depends on multiple variable but accounting for a quick estimate, roughly 1500-1800 square feet.
For those of you that don't understand the way AC systems work, a 2-ton unit typically provides cooling for about 900-1,400 square feet of space – give or take.
A simple formula for sizing air conditioners
Add your calculations for each room together to get the total square footage. Use the formula Total Square Footage x 25 to determine the required BTUs.
Homes measuring 1,000-1,500 square feet: You'll need a 2-ton unit, which corresponds to a cooling capacity of 24,000 BTUs per hour. Homes measuring 1,500-2,000 square feet: You'll require a 3-ton unit, equivalent to 36,000 BTUs per hour. Homes measuring 2,000-2,500 square feet: A 4-ton unit is necessary.
The Basic Rule of Thumb: 1-Ton AC Coverage Area
The concept is simple; if you know the square footage of the area you want to cool, you can quickly estimate the AC unit size in tons. For example, if you have a 1,200-square-foot home, the rule suggests that a 2-ton AC unit would be adequate.
For an Entire House
However, as a shortcut, most HVAC experts agree that you need a 1.5-ton (18,000 BTU) unit for a 1,000-square-foot space, a 2-ton unit for a 1,500-square-foot home, and one additional ton for every 500-square-foot increment.
The average cost of installing a new central air conditioner in 2024, including equipment and labor costs, is $5,750 for a 3-ton unit in a 2,000-square-foot home. On average, a new AC unit cost will fall between $3,300 and $7,800.
To estimate your AC tonnage needs, multiply the number of square feet you're cooling times 25.
For most homeowners: Hot Climates (Texas): A 17-18 SEER unit with a variable-speed compressor provides a great balance of comfort, efficiency, and cost. Milder Climates: A 14-16 SEER unit is often sufficient.
First, if the system is too small for the space it is intended to cool, there may be inadequate cooling and an inability to maintain a comfortable temperature. This could result in overworked components due to the excessive strain on the system, leading to higher energy costs and a shortened lifespan of the unit.
tonnage, in shipping, the total number of tons registered or carried or the total carrying capacity. Gross tonnage (GT) is calculated from the formula GT = K1V, where V is the volume of a ship's enclosed spaces in cubic metres and K1 is a constant calculated by K1 = 0.2 + 0.02 log10 V.
For a 100-130 square feet room 0.8 to 1 ton AC is enough. for a room of 130 square feet to 200 square feet of 1.5 ton AC is better. more than 182 200 square feet rooms require a 2 ton AC and more than 500 square feet rooms require more than one AC in multiple places.
Central AC Size Based On Your Home's Square Footage
1,400-1,600 square feet: A 24,000 BTUs (2 tons) AC unit is recommended. 1,600-1,800 square feet: Look for an AC unit with 27,000 BTUs (2.25 tons) for effective cooling. 1,800-2,000 square feet: A 30,000 BTUs (2.5 tons) unit is ideal for this square footage.
The cost of a 4-ton AC unit typically ranges between $4,000 to $5,500. However, this price can vary depending on factors such as the brand, model, energy efficiency rating (SEER), and additional features like advanced filtration systems or smart thermostats.
However, the truth is an oversized system will not do a better job of cooling the house or provide any extra comfort over a properly sized unit. Air conditioner size is calculated in BTU (British Thermal Units) and tons, and measures how much heat the system can remove from the home in one hour.
The thumb rule uses 500 square feet per ton to calculate the size of the air conditioning system. Although heavily used by HVAC companies across Gresham, Oregon, few other load calculator techniques may prove to be more accurate than the thumb rule in determining the right size of your air conditioning system.
The air now has to re-pressurize to regain its turbulent flow so it can continue to push its way down the duct. It requires about 24′ or two feet to do this. This is the 'Two-Foot Rule?. Ideally, you should allow at least 24′ between takeoffs and at the end of any duct run.
An air conditioner's model number is a string of numbers and letters. Within the string, you should see an even, two-digit number. Add three zeroes to the number and you have the BTU rating. Divide the two-digit number by 12, and you have the tonnage.
You also don't want to buy a model that's too powerful for a room. Sure, a 12,000-BTU air conditioner will cool a small space (150 square feet or less) quickly. But it might cool it too quickly, preventing it from removing some of the ambient humidity from the room and leaving the room damp.
The Temperature Outside
Most central air conditioners can cool a moderate-sized (3 to 4 bedroom) home by about 5 degrees every 3 hours. This means while it can take no more than a couple hours to lower the temperature to a comfortable range in the fall or autumn, it can take much longer in the summer.