How do you size a commercial HVAC system?
To determine the size of system you’ll need, divide the amount of Btu you need by 12,000. For example: 100,025 to 125,000 Btu is 8 to 10 tons. 125,025 to 150,000 Btu is 10 to 12 tons.
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How big should my air handler be?

For example, your home’s square footage total, including all floors and ceilings, is what determines what size what size HVAC unit you need. For every 500 BTUs required for your home, you will need approximately one ton of air conditioning or heating capacity (1 ton = 12,000 BTUs).
Does the size of air handler matter?
Does size really matter? When it comes to your air conditioning unit, the answer is YES! Don’t fall for the myth that bigger air conditioning units are better. In fact, they do not give you better results.
What CFM air handler do I need?
Answer #1: 350 – 400 CFM per ton of HVAC capacity. This answer of 350-400 cubic feet per minute for each 12,000 BTUs of AC cooling is optimal for the system to run efficiently while adequately cooling and dehumidifying the space.

How many square feet can a 5 ton AC unit cool?
How many square feet does a 1 – 5 ton air conditioner cool?
AC Unit Capacity (Ton) | Cooling Capacity Square Feet |
---|---|
3 Ton | 1,400 – 1,600 sq ft |
3.5 Ton | 1,650 – 1,800 sq ft |
4 Ton | 1,850 – 2,100 sq ft |
5 Ton | 2,400 – 3,000 sq ft |
How many BTUs do I need for a commercial building?
To achieve the base value of Btu Multiply the square footage by 25. Add 400 Btu for each occupant, and 1000 Btu for each window or door outside.
How do you calculate tonnage for HVAC?
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. Next, divide that number by 12,000 to determine the tonnage capability you need in your new air conditioning unit.
How many CFM is a 6 ton unit?
2,400 CFM
One of the most common CFM-related questions we get is this: “How many CFM per ton of cooling?”…How Many CFM For 1 – 6 Ton Units? ( Chart)
Unit Tonnage: | CFMs Required: |
---|---|
5.5 Ton Unit | 2,200 CFM |
6 Ton Unit | 2,400 CFM |
How many square feet will a 5 ton unit handle?
2401 – 3000 sf
Air Conditioning Square Footage Range by Climate Zone
ZONE 1 | ZONE 2 | |
---|---|---|
3 Tons | 1501 – 1800 sf | 1501 – 1850 sf |
3.5 Tons | 1801 – 2100 sf | 1851 – 2150 sf |
4 Tons | 2101 – 2400 sf | 2151 – 2500 sf |
5 Tons | 2401 – 3000 sf | 2501 – 3100 sf |
How many tons AC do I need for 1000 square feet?
On average you need 1 ton of cooling for every 1000 square feet of home.