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How Many Watts Does a 4-ton AC Unit Use? Power Consumption Explained

4-ton Air conditioner

Air conditioners take up a huge percentage of the power that the average house uses. They’re the second biggest energy guzzler after the water heater. Different units do require different amounts of power, however. The amount they require is based on a few different factors.

The size is a big contributing factor. However, not all 4-ton AC units have the same power input. The efficiency of the machine also matters. Luckily, we can know the exact efficiency of the machine thanks to the SEER rating, which is there to provide us with that exact information. The higher the SEER rating, the less energy an AC unit will use compared to its cooling power.

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Power Usage Comparision

To determine how much energy your unit uses, all you have to do is check the SEER rating of your machine. Then, compare it to this handy chart:

Seer Rating: Average Wattage (For 4-Ton AC)
14 SEER 3,429 Watts
15 SEER 3,200 Watts
16 SEER 300 Watts
17 SEER 2,824 Watts
18 SEER 2,667 Watts
19 SEER 2,526 Watts
20 SEER 2,400 Watts
21 SEER 2,256 Watts
22 SEER 2,182 Watts
23 SEER 2,087 Watts
24 SEER 2,000 Watts
25 SEER 1,920 Watts

Of course, these are all averages. Some units use more, while others use less. Your machine probably uses different amounts at different times. The maximum is often about 1,900 watts higher than the average. Keep this in mind when adding a generator to your home. You need quite a bit of energy to turn the AC on, but then it generally requires less (until it needs to turn on again).

Heating and air conditioning inverter on the side of a house
Image Credit: Christian Delbert, Shutterstock

What Size Generator Do I Need for a 4-ton AC Unit?

To run a 4-ton AC unit, you need at least a 17 KW generator. Of course, this assumes you’re only using it to run the AC. You’re likely wanting to run other things, too. You’ll need to add these other items to your energy needs and choose a generator that can run everything. Plus, it also helps to overestimate how much power you will use, as it is always nice to have some extra.

Running an AC is very energy-intensive. Therefore, if you’re planning on cooling your home, you’re probably going to need a pretty large generator.

Remember that getting the compressor started could require as much as 3x the average power consumption. Therefore, the generator must produce much more than the average to get your AC turned on.

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A 14-ton AC’s energy consumption will rely largely on the SEER rating of the AC. Different units will need different amounts of power depending on their efficiency. Some are going to be much more efficient than others. The SEER rating lets you see just how efficient a certain AC is, allowing you to determine how much energy it likely uses.

However, AC units require extra energy to turn on. One unit may require three times its usual energy consumption to start. Keep this in mind when purchasing a generator or calculating how much energy your AC unit will need.

Featured Image Credit: F. Muhammad, Pixabay

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