As a rule of thumb, you need 30,000 BTU
British thermal unit
The British thermal unit (BTU or Btu) is a traditional unit of work equal to about 1055 joules. It is the amount of work needed to raise the temperature of one pound of water by one degree Fahrenheit (Physical analogue: one four-inch wooden kitchen match consumed completely generates approximately 1 BTU). In science, the joule, the SI unit of energy, has largely replaced the BTU.
Air conditioning
Air conditioning (often referred to as A/C or AC) is the process of altering the properties of air (primarily temperature and humidity) to more comfortable conditions, typically with the aim of distributing the conditioned air to an occupied space such as a building or a vehicle to improve …
...
1 ton = 12,000 BTUs / hour.
| Typical BTUs Needed | ||
|---|---|---|
| Area (sq. ft.) | Room Type | Recommended BTUs |
| 100-300 | Bedroom or home office | 5,000-6,000 |
| 100-300 | Master bedroom or playroom | 7,000-8,500 |
| 350-650 | Living room, family room, or open plan | 9,800-12,500 |
What size central air conditioner do I need for my home?
However, the most preferred central AC sizes for residential homes range from 2 to 2.5-tonnage. HVAC load is a crucial parameter that every homeowner must consider before buying an air conditioner.
What is the square footage of an air conditioner?
Air Conditioning Square Footage Range by Climate Zone. 1 1.5 Tons. 2 Tons. 2 2.5 Tons. 3 Tons. 3 3.5 Tons. 4 Tons. 5 Tons. ZONE 1. 600 - 900 sf. 901 - 1200 sf. 1201 - 1500 sf. 1501 - 1800 sf. 1801 - 2100 sf. 2101 - 2400 sf. 2401 - 3000 sf. ZONE 2.
How many tons of AC do I need for 600 sq ft?
The simple answer is basically for every square foot, you need 0.0016 tons. In mathematical terms: 600 sq ft x 0.0016 tons/sq ft = 1 Ton. To put it simply: AC Capacity (Tons) = (SQUARE FOOT) X 0.0016/SQ FT.
Do air conditioners come in different sizes based on room size?
The air conditioner sizes (BTU) are rounded to the actual common air conditioner sizes rather than just the result of the calculated cooling capacity. Hence, you can conveniently match the exact air conditioner based on your bedroom size. Below is a room air conditioner sizing chart by room type.
What size central air conditioner do I need for a 1500 sq ft home?
Step 5: Match your square footage to an HVAC size chartHome Sq FootageAir Conditioner Size (tons)600 - 1,000 square feet1.5 tons1,000 – 1,500 square feet2 tons1,500 – 2,000 square feet3 tons2,000 – 2,500 square feet4 tons1 more row
How many square feet will a 3 ton central AC unit cool?
1,800 square feet3-ton is equal to 36,000 BTU. If you apply the 20 BTU per sq ft rule of thumb, you can see that a 3-ton air conditioner cools about 1,800 square feet spaces.
How do I calculate what size air conditioner I need?
To calculate the size of the air conditioner you need for a room, first, multiply the length of the room with its width. Then multiply it with 25 BTU to get the ample cooling for the room under different weather conditions. For example, if the room is 15 feet long and 12 feet wide, it comes to 180 square feet.Nov 12, 2019
How big of a central air unit do I need for a 1600 sq ft house?
2.5 TonsZONE 1ZONE 31.5 Tons600 - 900 sf600 - 1000 sf2 Tons901 - 1200 sf1001 - 1300 sf2.5 Tons1201 - 1500 sf1301 - 1600 sf3 Tons1501 - 1800 sf1601 - 1900 sf3 more rows
Is 3 ton AC big enough?
Pro Tip: as a rule of thumb, the maximum AC unit size you need to install should not be more than 15% more than the BTU's you need to cool your house. This means that if your house requires a 24,000 BTU unit (2 tons), you should not install one that is larger than 30,000 BTU's (3 tons) to maintain energy efficiency.
How much is a 3 ton AC unit cost?
A 3-ton AC unit cost runs homeowner around $3,400 to $3,700. When it comes to a 3.5-ton AC unit cost, you will pay around $3,500 to $3,700. A 4-ton AC unit cost is $3,700 to $3,800 on average. When it comes to a 5-ton AC unit cost, you will see pricing around $3,800 to $4,000.Jun 3, 2021
What size air conditioner do I need for a 3500 square foot house?
Many homes especially in warm climates have more than one central air conditioner. For example, consider a 3500 square foot home in Zone 2 with a Very Sunny rating. It would need between approx. 76,000 and 104,000 BTUs of cooling!
What size AC do I need for 1200 sq ft?
STEP 1: Determine how many BTUs of heating and tons of AC you needHouse Square FootageBTUs Needed500 – 70014,000700 – 1,00018,0001,000 – 1,20021,0001,200 – 1,40023,00010 more rows
What size AC do I need for 1700 sq ft?
Furnace and Air Conditioner size for a detached 2-storey homeHouse square footage *Furnace Output [BTU/hr]Air Conditioner size [ton]up to 1300 sq ft40,000 BTU/hr1.5 ton1300 to 1700 sq ft45,000 BTU/hr1.5 ton1700 to 2500 sq ft55,000 BTU/hr2 to 2.5 ton2500 to 3500 sq ftup to 65,000 BTU/hr2.5 to 3 ton3 more rows•May 26, 2017
What size air conditioner do I need for a 1300 sq ft house?
When looking for the quick answer to how much air-conditioning power you'll need to adequately cool a 1,300-square-foot space, the answer is 23,000 BTUs per hour of air conditioning power. This is the base capacity needed for a 1,200- to 1,400-square-foot house.Sep 27, 2021
What size central air conditioner do I need for a 3000 sq ft home?
5-tonThe recommended capacity for a home that is 1,201 to 1,500 square feet is 2.5 tons. For a home 1,501 to 1,800, the recommended capacity is 3 tons. For a 2,000 square-foot home, the best AC capacity is 3.5 tons. Since larger homes are costlier to cool, you'll need a 5-ton unit to cool a 3,000 square-foot home.
What size AC unit do I need for a 1800 sq ft house?
3-tonHere's some math: You need around 20 BTUs per square foot, which is equivalent to 0.0016 tons. For example, a 600-square-foot space requires a 12,000 BTU or 1-ton unit. By those calculations, an average 1,800-square-foot house would need a 3-ton central air conditioning unit.Nov 24, 2021
What Does Central Air Conditioner Sizing Mean?
The term “size” of a central AC unit does NOT refer to the physical dimensions. Rather, AC unit size is a measure of its capacity to generate cool...
Manual J: Professional AC Unit Size Calculation
To get a truly accurate size of a central air conditioning unit that will work most efficiently in your house, you need to get a professional load...
Factors That Impact How Big of An AC Unit You Need
As you may have already guessed there are a number of important variables that will effect the size of a central air unit your house requires. Tota...
Why It’S A Bad Idea to Install The Wrong Size Central Air
It is important to understand exactly why it is not advisable to install the wrong size central air, whether too big or too small.
Types of air conditioning systems
Before sizing your air conditioner to your home’s needs, determine what type of system you want to install. There are a variety of cooling systems available, but we’ll cover the three primary styles below. (Looking for how to properly size a window AC ?)
How many BTU per square foot?
A BTU, or British Thermal Unit, is a rating that measures the energy your AC uses in one hour to remove heat from your indoor air. The BTU of your HVAC system should be based on the square footage of your home, insulation quality, climate zone, and ductwork.
Manual J calculation
A Manual J calculation is like an energy audit of your home. Who performs the Manual J calculation can vary depending on your region. In some instances, the HVAC company will complete the audit. It’s also possible for a general contractor or energy consultant to complete the work.
AC climate zones
While the square footage and makeup of your home will give you great direction on sizing your HVAC unit, we can’t forget climate.
Best HVAC size for your home
Choosing the right size air conditioning system for your home doesn’t have to be complicated.
How many tons of AC should I use for a 600 sq ft house?
In general, you should have approximately 1 ton of ac capacity to cool 600 sq.ft. of area. (600 sq.ft./1 ton). This estimate is most accurate in new construction or newer homes that have proper insulation. In older homes, many factors will skew this estimate, and you may require a larger ac unit size to cool your house, ...
How to get accurate size for central air?
To get a truly accurate size for central air that will work most efficiently in your house, you need to do a professional load calculation , known as “the Manual J”. Most HVAC installers include it for free as part of their estimate, when they give you the total cost to install central air in your home.
How much does it cost to install a 2.5 ton central air system?
Before we get into sizing a residential central air unit, lets take a quick look at pricing. On average, homeowners report spending $3,900 – 5,000 to install a 2.5 ton central air system in a house that has functional ductwork.
How much does a 5 ton AC unit cost?
5 ton AC unit costs $2,900 – $3,500 ( a 5 ton unit is extremely powerful and is not required for most homes) In general, you can roughly add $400-$700 for each additional ton, as the units go up in size. Residential Central AC systems come in a maximum size of 5-ton.
How do AC units save energy?
Today, new air conditioner units are energy efficient. This means that they save energy by running in cycles, which results in your home being cooled at a slow and steady, rather than a rapid pace. Because of this change in how the AC unit operates, its essential to get one that is just the right size for your house.
What happens if your AC unit is too small?
AC unit that is too small 1 Will not keep your house at a comfortably cool temperature on the hottest days 2 Uses a lot of energy 3 Has to run all the time 4 Running all the time instead of cycling will drastically increase your electric bill
Can I use a commercial roof top AC for residential use?
Anything bigger, requires a commercial roof-top AC, which are in most situations not suitable for residential use. Final pricing for central AC also varies based on brand name, as well as other features. Its best to purchase a unit from a well known, reputable manufacturer that offers a very good warranty.
Table of Contents
An air conditioner’s primary purpose is to cool down your home. However, using one that doesn’t match the square footage of your home will struggle to keep a room at a comfortable temperature. The right-sized air conditioner will give you the best results in comfort, performance and energy efficiency.
Air Conditioner Ratings
Air conditioners are typically rated in two ways: cooling capacity and energy efficiency.
Variables That Might Impact the Size of Air Conditioner
The main factor for choosing the right sized air conditioning system is the square footage of your home. However, there are some other variables that come into play which can affect how efficiently your system can cool.
How to Calculate Size
To calculate the size of the unit you will need, you will need to know the square footage of the room or house. To find the square footage, multiply the length times the width of the rooms in your home, then add them together. Once you have the square footage, multiply it by 25 to get the BTUhs needed to cool your space.
Existing Ductwork
The size of your air conditioning unit must be compatible with your ductwork. The wrong sized ducts will cause similar problems to having an improperly sized AC unit for your square footage. Improperly-sized ductwork puts too much pressure on your unit.
HVAC Pros
Although it’s important to understand how to pick the right size air conditioner for your home, an HVAC professional will perform all the calculations necessary for maximum efficiency.
What Is a Cooling Load?
The amount of cooling required to lower the temperature in a home is commonly referred to as the load or cooling load (the amount of heating required is called the heating load). The cooling load relates to the demand of the home, but it directly translates to the output, or capacity, of the air conditioner.
Calculating Air Conditioning Load
HVAC contractors generally use more complicated methods, but you can make some ballpark calculations of the air conditioning load needs for your home using simple variables, such as the square footage of the area to be heated. Be aware, though, that such a method gives you only a ballpark estimate of your cooling needs.
Online Load Calculators
For a more precise air conditioning load calculation, you can use any number of online calculators, which are commonly offered by air conditioner manufacturers and HVAC trade organizations. These calculators work by asking a series of questions that assign values to the variables that affect cooling load.
Manual J Calculations
Until the Air Conditioning Contractors of America (ACCA) created the Manual J method in 1986, HVAC contractors used a variety of rule of thumb estimates to determine how much heating and cooling a home needed.
Why Proper Sizing Is Important
You might think that an air conditioning system that is extra large might somehow be more efficient or durable than one that is undersized, or that a small system might somehow be cheaper to run. However, in practice, it's important for the system's capacity to be quite close to the load demand as determined by the Manual J calculation.
Other Guidelines Used by Contractors
Manual J calculation is the required method used by HVAC contractors to determine the Btu load that an air conditioning system must meet, but it is not enough to simply pick equipment that meets this calculation.
Why does my air compressor short cycle?
If the system you install is too large for the space, it will short cycle. In other words, the compressor will not run long enough to dehumidify the space and will limit your comfort. In addition, it will cycle on and off more frequently, increasing operating costs and reducing the system life.
Does the manufacturer list the size of an air conditioner?
The manufacturers do not list the air conditioner size on the unit. The system capacity will be coded into the model number of the outdoor unit. For example, model GSX140241K is a 2 ton unit.
Table of Contents
Click on the below link to jump to your preferred section on this page.
Common Residential Air Conditioner Sizes
Below is a table of common residential air conditioner sizes in 4 different units of measurement for cooling capacity (BTU, Ton, HP and kW). These different units of measurement don’t translate mathematically. They are listed based on commonly available sizes. Hence, you should not use this table for unit conversion.
Common Central Air Conditioner Sizes
Below is a table of common central air conditioner sizes in 4 different units of measurements for cooling capacity (BTU, Ton, HP and kW). Again, these different units of measurement don’t translate mathematically. They are listed based on commonly available sizes. Hence, you also should not use this table for unit conversion.
Room Air Conditioner Sizing Chart by Room Size
Below is a room air conditioner sizing chart by room size. The air conditioner sizes (BTU & Ton) are rounded to the actual common air conditioner sizes rather than just the result of the calculated cooling capacity. Hence, you can conveniently match the exact air conditioner based on your room size.
Room Air Conditioner Sizing Chart for Bedrooms
Below is a room air conditioner sizing chart for bedrooms. The air conditioner sizes (BTU) are rounded to the actual common air conditioner sizes rather than just the result of the calculated cooling capacity. Hence, you can conveniently match the exact air conditioner based on your bedroom size.
Room Air Conditioner Sizing Chart by Room Type
Below is a room air conditioner sizing chart by room type. The air conditioner sizes (BTU) are rounded to the actual common air conditioner sizes rather than just the result of the calculated cooling capacity. Hence, you can conveniently match the exact air conditioner based on your type of room and its respective square footage.
Air Conditioning Sizing Chart by Total Square Footage
Below is an air conditioner sizing chart by total square footage. The air conditioner sizes (BTU & Ton) are rounded to the actual common air conditioner sizes rather than just the result of the calculated cooling capacity. Hence, you can conveniently match the exact air conditioner based on the square footage of any room, house or home.
How to measure the size of an air conditioner?
Generally, the size of air conditioners can be measured by two units, tonnage and BTU (British Thermal Unit) per hour. Here are their definitions: The amount of energy required to increase the temperature of one pound of water by one ℉ is equal to 1 BTU.
What is the insulation level of a room?
The insulation level refers to the temperature retaining power of a space. It directly depends on the thermal insulation of the material used to build the walls and the number of external openings, such as windows. The higher the insulation level of your room, the lesser the need to install a larger AC system.
How many BTUs per hour for 1 ton of ice?
1 Ton is the amount of energy required to melt a ton of ice in twenty-four hours. For a simple approach, you can take 1 ton = 12,000 B TUs per hour for direct load calculations. Another crucial factor that helps in determining the accurate AC sizing is the cooling load of your home.
How much faster does a house cool with 2 windows?
Comparatively, a house with two windows will cool much faster with a 2.5 ton AC unit than a space with four windows.
Can you pick up AC for your home?
Lastly, if you can calculate the BTU and load of your property, you can easily pick up the right AC system for your home. For beginners, this job might feel a bit technical, but if you refer to the calculations mentioned above and instructions, AC shopping will feel like a breeze.
Do small rooms need AC?
Smaller rooms do not need large AC systems to maintain a comfortable temperature. On the other hand, bigger rooms demand an HVAC system, which is stronger because of the increased BTU requirement.
Is a 5 ton AC enough for a room?
For a room with poor insulation, even a 5 ton AC is not enough for cooling.
How many square feet does an AC unit cool?
AC systems to efficiently cool 2000 square feet.
Can you have a central AC unit outside?
This comes with the benefit of being placed outside of the house, meaning that you don’t have to worry about venting recycled air into your home.
Do AC units work?
Many AC units need to work for a specific size of the house. The bigger the house, the bigger the AC. They do this to regulate airflow and air cycling. Without a properly sized machine installed in the correctly scaled house, all you get is a machine that sputters and smells like rotten eggs. For a house of 1200 feet, what is ...
How much power does an air conditioner need?
When looking for the quick answer to how much air-conditioning power you'll need to adequately cool a 1,300 square foot space , the answer is 23,000 BTUs per hour of air conditioning power. According to the government's Energy Star website, this is the base capacity needed for a 1,200 to 1,400 square feet house. You should also look for a unit that has at least an 11.6 Seasonal Energy Efficiency Ratio that determines how efficient your system is in the hottest weather. Manufacturers only produce air conditioners with a SEER rating of 13 or higher today, so new units exceed this minimum requirement.
Does square footage matter when choosing a central air system?
The square footage in your home is not the only factor that matters when choosing a central air system. Consider other variables that could make your home tougher or easier to cool. A heavily shaded home may require 10 percent less energy to cool. On the other hand, lots of windows, little shade and a sunny climate may have the opposite effect. If a kitchen is used regularly for cooking, then it can also significantly increase the energy needs for cooling.
Is it bad to have a central air conditioner?
But having an improperly sized central air conditioner has negative effects regardless of whether it has too much or too little capacity. Too little capacity means the air conditioner will have to run constantly to cool the house and will cause higher electric bills and potentially a home that is too warm. If the central air unit is too large it will cool too fast, run short cycles and not remove the humidity from the air, which is a significant part of the air conditioning process.
