What Size Breaker For 3 Ton AC?

Disclosure: We may get commissions for purchases made through links in this post.

Installing an air conditioner involves more than just the unit itself. You'll need to make sure your breaker can handle the unit. But what size breaker do you need for a 3-ton air conditioner? We researched this question for you, and here is what we discovered.

For 3-ton AC units, the breaker size is typically 30-40 amp. However, the breaker size will ultimately depend on the manufacturer's recommended ampacity. 

In this article, we'll see why breaker size matters, how to compute breaker size, and the correct breakers for other sizes of AC. We'll also cover topics such as the correct wiring to use and what might cause a breaker to trip. Read on to learn more about each of these issues. 

Electrician Wearing Gloves Doing testing in Circuit Breaker, What Size Breaker For 3 Ton AC?

Why Does Having The Right Breaker Size Matter In AC Installations?

When checking an electrical panel, one of the first things home inspectors do is compare wire sizes to circuit breaker sizes. You have a possible fire hazard when a wire is too tiny for a circuit breaker. Overheating of the wires is prevented by circuit breakers.

How To Compute AC Breaker Size

Ac Breaker and circuit wires

If you buy a circuit breaker that is too small for your air conditioner, it will trip the breaker every time it needs too much current. To know what breaker size you should use, you can follow these steps to compute the breaker size: 

  1. Check the wattage of your air conditioner on its specification sheet. Make a note of the maximum wattage it consumes.
  2. Look at the specification page for the air conditioner's needed voltage. Check the plug on the air conditioner if you don't see a voltage requirement. Remember, if it has a standard household plug with three straight prongs, it requires 120 V of power.
  3. Divide the wattage number (from the 1st step) by the voltage (from the 2nd step). This will tell you how many amps your circuit breaker must withstand.

List Of Air Conditioning Units Capacities And Their Breaker And Wire Sizes

Listed below are different air conditioner units' capacities with their respective breaker size and wire size: 

  • 1 Ton AC - 15 amp breaker; AWG 14 wire
  • 1.5 Ton AC- 20 amp breaker; AWG 12 wire
  • 2 Ton AC- 25-30 amp breaker; AWG 10 wire
  • 3 Ton AC- 30-40 amp breaker; AWG 8 wire
  • 4 Ton AC- 50-60 amp breaker; AWG 6 wire
  • 5 Ton AC- 60-70 amp breaker; AWG 4 wire

Should Air Conditioners Have A Dedicated Circuit Breaker?

Before purchasing or even plugging in an air conditioner, determine whether it needs its circuit breaker.

One rule of thumb is that air conditioning units with a BTU of over 15 000 will almost certainly require a specialized circuit breaker with a specified voltage rating.

Why Should You Have A Dedicated Circuit Breaker For Your Air Conditioner?

Specific appliances, such as HVAC systems, have their specialized circuit breaker.

Because these appliances will consume a significant amount of electricity, connecting them to dedicated circuit breakers ensures that they have adequate power to run properly and without suffering any electrical issues that could impede their performance and efficiency.

How To Know If There Is A Dedicated Circuit Breaker For Your Air Conditioner?

To check, you can do these steps to determine if you already have a dedicated circuit breaker for your AC: 

  1. Examine your breaker box. A label saying "air conditioner" or "AC" should be present if a dedicated circuit was installed in your home and properly labeled. 
  2. Check the plugs where some of these appliances are plugged in if none of the panels are labeled. These outlets may be on a dedicated circuit if they aren't ordinary 120-volt receptacles.
  3. You likely don't have a dedicated circuit breaker if your main circuit breaker keeps tripping when you use multiple appliances at the same time or when you switch on your air conditioner.

What Are The Benefits Of Having A Dedicated Circuit Breaker For Your Air Conditioner?

Dedicated electrical circuit breakers provide you with the peace of mind you need to experience the best of your air conditioning equipment without having to worry about electrical trips on hotter days.

In addition, they'll keep your appliances, family, and the rest of your house safe.

Causes Of AC Breaker Tripping

Have you ever experienced having your AC breaker tripping? If yes, here are some possible reasons why it happened:

  • Clogged Air Filter
  • Dusty Condenser Coils
  • Damaged Coil Fan
  • Hard Starting Compressor
  • Loose Wiring 
  • Low Refrigerant Charge
  • Use of GFCI Type of Breaker
  • Use of Tandem Breaker instead of a Double-Pole
  • Shorted Motor

Clogged Air Filter

Ac Filter Clogged full of dust

One of the most common causes of an AC system tripping the circuit breaker in a home is when the filter becomes clogged. When an air conditioner's filter becomes clogged, the machine has to work extra hard to blow out cool air. As a result, the air conditioner will use more energy.

In some circumstances, increased power usage causes too much electrical current to flow through the circuit breaker wiring, causing the system to shut down for safety.

Dusty Condenser Coils

The heat received through the interior unit is removed by the condenser coils on the outer unit of your air conditioner. Because of their exposure to the outdoors, these coils can get dirty over time.

The exterior unit will not be able to release the stored heat outside your home or business if the condenser coil becomes too dusty. As a result, your system will have to work harder to cool your space, potentially causing your circuit breaker to trip due to an overload of electricity.

Damaged Coil Fan

Ac coil cleaned and checking for maintenance

A damaged coil fan could be to blame if your air conditioner fan motor is tripping the breaker because it isn't getting enough electricity from your circuit.

This problem can be caused by broken or missing elements of an air conditioner, resulting in higher electrical demand and probable breaker trips.

Hard Starting Compressor

The compressor is an important component of your air conditioner, and as it ages, it may have trouble starting up. If the circuit breaker continues to trip, an HVAC expert should examine the flow of power between the fan and the circuit.

Loose Wiring 

Your air conditioner is a tangle of wiring that keeps the whole system running. These wires may get loose and lose their contact over time, causing your circuit breaker to trip occasionally.

Low Refrigerant Charge

A lack of refrigerant might also cause your air conditioner to utilize too much energy, causing your circuit breaker to trip. While refrigerant does not deplete and does not need to be replaced throughout the AC system's life, leaks might cause low refrigerant levels.

Refrigerant levels will drop if your condenser coils develop cracks, holes, or other types of damage, and your system will have to work harder and longer to cool your area.

Use of GFCI Type of Breaker

Automatic Circuit Breaker

Adding a GFCI breaker to your system could seem like a good idea at first to boost the level of safety. Most inverter systems, on the other hand, are incompatible with GFCI breakers.

Due to the way inverters operate electrically, if the GFCI isn't rated for high voltage at the electrical frequency in which the system operates, it can trip very easily.

A standard breaker with an AC disconnect box is usually sufficient for safety.

Use of Tandem Breaker instead of a Double-Pole

On a 230V system, using a tandem breaker when a double-pole type is nearly always required is a typical installation blunder.

A tandem breaker provides two 115V circuits and a double-pole breaker provides one 230V circuit. A 230V system isn't meant to function on a tandem breaker, and it could not even turn on.

Shorted Motor

Another possibility is that the motor within your air conditioner has shorted and is triggering the circuit breaker.

The motors in AC units may usually run for a long time. They do, however, have limitations. When an AC motor operates for too long, the wire insulation can break down, resulting in an electrical short.

When energy bypasses its typical course, more electricity passes through than the wire can handle, causing a short. As a result, the wires will overheat, causing your circuit breaker to trip to prevent a fire.

Final Thoughts

Electrician Wearing Gloves Doing testing in Circuit Breaker

If you have a 3-ton AC unit, then your breaker size should be 30-40 amp and the wire size should be AWG 8. It is best to look for the manufacturer's specification on what size of breaker you should use. 

Having the right breaker size is an integral part of a successful HVAC system. Not only does it provide safety from fire and shorts, but it also offers convenience since you don't have to constantly worry about it. 

If you want to learn more about generators running an air conditioner, you can check these articles before you leave: 

9 Best Generators For Running An Air Conditioner

What Size Generator Can Run A 5000 BTU Air Conditioner?

Leave a Reply