Using a 3 Ton AC | 7 Answers you Should Know

Considering using a 3 Ton air conditioner with a cooling capacity of 36,000 BTU to keep your house cool?

There are several important points to keep in mind to use the AC reliably, safely while also getting the most out of it.

This includes knowing the size of area it is suited to cool, how much energy and electricity it uses as well as suitable wire gauge and circuit breaker to use with it.

So in this post, I share the estimated cooling area for the air conditioner, indicative energy and electricity usage, and also the recommended circuit breaker, and wire size rating for a 3 Ton air conditioner.

#1. How Many Amps a 3 Ton Air Conditioner Uses?

A 3 Ton, 208 – 230V Air Conditioner has an estimated current draw of up to 30 – 35 amps. At startup, the current draw rises considerably but for a short while before reducing.

Even then, the actual current draw for the AC varies depending on the user settings selected such as the speed of the fan and the target temperature to cool too.

The higher the fan speed is for example, the higher will be the current drawn by the air conditioner.

#2. How Many Watts to a Run 3 Ton AC Unit

The estimated power consumption of a 3 Ton AC at full load is about 3,730 watts.

This power consumption is considerably higher during the startup phase of the air conditional before reducing later.

This assumes a cooling efficiency rating of 18 (SEER).

More efficient units will consume less while the inefficient ones will use more.

#3. What Size of Circuit Breaker to Use

A 3 Ton air-conditioner likely requires a circuit breaker with a current rating of 35A.

Nonetheless, always consult the technical specification information for your AC model.

#4. What Size of Wire for The 3 Ton Ac Unit

As a guide, use 10 AWG wire size as a minimum when wiring a 3 Ton AC rated, 208 – 230V. These units usually have a specified minimal ampacity of 23A.

Nonetheless, always consult the technical specification documentation for your AC model.

#5. What Size of Generator You Need for A 3 Ton AC Unit?

To power your AC, you can use a good quality 10kVA rated generator or higher.

This assumes that the generator is dedicated to powering the AC.

Should it be supplying power to other appliances, consider using a generator with a higher capacity to avoid overloading it.

Also, beware of poor-quality generators – these tend to be overrated and can fail to power the 3 Ton AC.

#6. How Many Square Feet for A 3 Ton AC Unit?

The area that can be cooled by a 3 Ton AC unit effectively depends on the prevailing climate of the area where it is being installed.

Besides the climate, there are additional considerations that are factored in the decision of whether a 3 Ton AC is suitable for cooling an area such as:

  • how much window space is available. When there are fewer windows, less cooling is required.
  • how well insulated the building. Rooms with good insulation need less cooling.

That said, a 3 Ton AC can cool an estimated area of 1,500 – 2,060* square feet.

In locations with warmer climate, the area that can be effectively cooled reduces and increases for locations with colder weather.

For cooling a whole house, consider a residential split-system central AC with ducts for each of the various rooms to be cooled.

*Note: These are estimates and you should consult a professional to size the AC for your desired space before you decide to purchase and install the AC.

Related Questions

#7. Should you use 3 Ton or 3.5 Ton AC?

Are you wondering whether to use a 3 Ton or a 3.5 Ton AC?

While you may be tempted to go for a 3.5 Ton AC, after all its cooling capacity is over 15% more than that of the 3 Ton AC.

For an existing installation, it is worth considering as a first step, what might have changed for the existing AC to stop cooling effectively.

  • Is it a case of lack of regular maintenance?
  • How well insulated is the areas you want cooled?

Addressing issues of lack of maintenance or poor insulation can save you time and money when you buy a new unit.

Does the unit struggle to cool at all times or during times when there is a large gathering?

It is advisable to consult an AC professional or contractor to conduct a professional heat load assessment to guide whether a 3 Ton or a 3.5 Ton AC is a better choice.


A 3 Ton AC with its cooling capacity of approximately 36,000 BTU can cool a room of 1,500 – 2,060* square feet (estimate) depending on the insulation of the building and climate where it is installed.

At full load, the AC draws approximately 3,730 watts. Actual power consumption varies depending on the settings selected.

For overcurrent protection of the AC, as a guide consider using a circuit breaker with a current rating of 35A.

Related Posts

Leave a Comment