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 the correct AC size, then?
I know that math is troublesome for those who struggled within the school, but thankfully, there’s a guide. For a house of 1200 square feet, it’s best to consider AC units that are 23,000 BTUS in power. BTUs meaning British Thermal Units of Heating. (Gotta love the Brits).
| House Square Footage | BTUs Needed |
| 100 – 150 | 5,000 |
| 150 – 250 | 6,000 |
| 250 – 300 | 7,000 |
| 300 – 350 | 8,000 |
| 350 – 400 | 9,000 |
| 400 – 450 | 10,000 |
| 450 – 500 | 12,000 |
| 500 – 700 | 14,000 |
| 700 – 1,000 | 18,000 |
| 1,000 – 1,200 | 21,000 |
| 1,200 – 1,400 | 23,000 |
| 1,400 – 1,500 | 24,000 |
| 1,500 – 2,000 | 30,000 |
| 2,000 – 2,500 | 34,000 |
Load Calculation
The load calculation for your home is how much air works through your home and must be considered to get the proper machine.
There are a few factors that can affect the load calculation, such as:
- Your home’s construction materials.
- The number of windows.
- The size of the rooms.
- Your home’s insulation levels.
Each of these affects how the Air Cycles. Like how an open window causes air to flow both in and out more easily.
Your home’s insulation, how well it can retain heat can also affect air cycling.
Construction, wood vs stone vs plastic, will naturally affect the temperate of the air.
And the number of rooms will cause air to be moved into each of them, once again affecting the airflow.
BTUS Calculation Formulas:
So, think of tons to BTUs in factors of 12. 2 tons is 24,000, 3 is 36,000, and so on.
But what about tons to square feet? That’s important too. Well, unfortunately, yes. The simple answer is basically for every square foot, you need 0.0016 tons. To make a formula: 600 sq ft x 0.0016 tons/sq ft = 1 Ton.
For reference, 12,000 BTUs translates to 1 tonne of equipment, and 36,000 BTUS is 3 tonnes.
So, think of tons to BTUs in factors of 12. 2 tons is 24,000, 3 is 36,000, and so on.
Tons to square feet calculation
But what about tons to square feet? That’s important too. Well, unfortunately, yes. 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.
But, let me write you a table for a quick reference.
BTUS Tables:
To correctly calculate the BTUs, however, you need to find a calculator and take measurements of your home and ceiling height. As nice as it would be, you can’t just go to the nearest store and buy one just like that.
Let me show you a quick table.
BTU to Tons Table
| Tons | BTUS |
| 1 | 12,000 |
| 2 | 24,000 |
| 3 | 36,000 |
| 4 | 48,000 |
| 5 | 60,000 |
Tons to square feet calculation
But what about tons to square feet? That’s important too. Well, unfortunately, yes. 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.
But, let me write you a table for a quick reference.
Tons to Sq Ft Table
| Tons | BTU | Area (Square Feet) |
| 1 | 12,0000 | 600ft |
| 2 | 24,0000 | 900ft |
| 3 | 36,0000 | 1,200ft |
| 4 | 48,0000 | 1,500ft |
| 5 | 60,0000 | 1,800ft |
| 6 | 72,0000 | 2,100ft |
| 7 | 84,0000 | 2,400ft |
Importance of Choosing the Right Size Unit
So, I take it by now you understand just how important it is to choose the right size of an AC unit? There’s a lot of math involved, but it’s worth it. If you don’t choose the right size, after all, the AC unit won’t work or might overcompensation if it’s too big for a small house.
AC systems to efficiently cool 2000 square feet.
But what about AC units for 2000sq ft? Are there any good ways to keep those kinds of homes cool? Well, yes, there are two main choices to choose from. The Central AC unit and the mini-split system.
Central AC – Pros and Cons
You can have a central AC unit that acts as the ‘main station’ where the primary air cooling and cycling occur, where all the other ac units act as substations.
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.
But, at the same time, they cost quite a bit and require a hefty installation process to install. And since they are exposed to the elements, there is a chance something might affect them outside of your control. A bird, for example, could land in the system and wretch things up.
And, again, there’s always going to be quite a bill with these kinds of machines. But, hey, you don’t have to turn them on all the time.
Mini-split systems – Pros and Cons
A mini-split system well splits the process into two sections. An outdoor and indoor one. The outdoor system has the condenser and compressor, while the indoor contains the evaporator.
This means this system is the most economical to install and can work even if you don’t have a furnace.
At the same time, this requires a lot of energy, so expect a bill in the mail. Plus, you need to make sure both systems are running instead of just one. So you’re doing double duty for a single machine.
So, yeah, we’ve covered most of what you need to know for AC units and how to choose the best one for your home. I hope this guide was of some help to you!
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