# What Size Generator To Run 3 Ton AC Unit? Our 5 Suggestions

*We have provided the derailed answer to the highly searched question “What Size Generator To Run 3 Ton AC Unit with great examples and data”. Read this article to the end to find the top 5 generators for 3-ton AC units as well. *

A generator that is too small can lead to problems with starting the AC’s compressor, while an oversized generator can result in unnecessary expenses and energy waste.

To calculate the appropriate generator size, it is necessary to consider both the power requirements of the AC and the generator’s capabilities.

In this discussion, we will delve into the factors involved in determining the optimal generator size for a 3-ton AC unit, presenting a well-informed and engaging analysis of the topic.

## What Size Generator To Run 3 Ton AC Unit at Home?

**A typical 3-ton AC unit requires a starting current of about 35 amps and a running current of 18-20 amps, both at 240 volts. This translates into a peak power demand of approximately 8,400 watts and a sustained power demand of 4,320-4,800 watts.**

Selecting a generator that can supply these power requirements with stable voltage and frequency stability is essential for optimal performance and reliability.

### What Size Generator to Run 3 Ton Single Phase AC Unit?

Single-phase AC units typically require a starting current of **35-45 amps** and a running current of 18-20 amps, both at 240 volts.

This corresponds to a peak power demand of approximately 8,400 watts and a sustained power demand **of 4,320-4,800 watts**.

To ensure reliable operation, the generator should have a capacity of at least **9,000-10,000 watts**, sufficient voltage regulation, and low total **harmonic distortion**. Proper sizing of the generator and wiring also requires knowledge of local electrical codes and standards.

Here is the guide about What Size Generator To Run An Air conditioner in general.

### What Size Generator to Run 3 Ton Three Phase AC Unit?

AC’s power requirements typically include a starting current of **35-45 amps** and a running current of **18-20 amps per phase**, at either 208 or 240 volts.

This corresponds to a peak power demand of approximately 10,000-12,000 watts and a sustained power demand of **5,040-5,760 watts.**

A generator with a capacity of at least **12,000-14,000 watts,** three-phase output, and proper voltage regulation and frequency stability is recommended for reliable operation.

Other factors that should be taken into account when choosing a generator for a three-phase 3-ton AC unit include its efficiency, **noise **level, and fuel type.

Additionally, proper sizing and wiring of the generator must comply with local electrical codes and standards to ensure safety and reliability.

### Will a 10000-watt Generator Run a 3-ton AC Unit?

A 3-ton AC unit typically requires a starting current of 35-45 amps and a running current of **18-20 amps per phase**, at either **208 or 240 volts.**

The peak power of approximately 10,000-12,000 watts and the continuous power of **5,040-5,760 watts.**

A **10,000-watt generator** may be able to handle the sustained power demand of a 3-ton AC unit, but its capacity may not be sufficient to handle the unit’s high starting current demand.

However, this may depend on the specific make and model of the AC unit, as well as the generator’s capabilities.

**For example**, if the 3-ton AC unit has a starting current of **35 amps** and a running current of 18 amps per phase, a 10,000-watt generator could potentially supply enough power to meet the unit’s demands.

However, if the AC unit has a starting current of 45 amps, a generator with a capacity of at least 12,000 watts or higher would be recommended to ensure reliable operation.

We have also written a guide about **What appliances can a 10,000-watt generator Run?**

*Here are some examples.*

**Example 1**:

A 3-ton AC unit requires a starting current of 35 amps and a running current of 18 amps per phase, at 240 volts.

This corresponds to a peak power demand of 8,400 watts and a sustained power demand of 4,320 watts.

A 10,000-watt generator may be sufficient to handle the unit’s power requirements, if it is properly sized and wired, and has adequate voltage and frequency stability.

**Example 2:**

A 3-ton AC unit requires a starting current of 45 amps and a running current of 20 amps per phase, at 208 volts.

This corresponds to a peak power demand of 11,760 watts and a sustained power demand of 5,760 watts. In this case, a 10,000-watt generator would be insufficient to handle the unit’s high starting current demand, which could result in compressor damage or reduced AC unit performance.

A generator with a capacity of at least 12,000 watts or higher would be recommended to ensure reliable operation.

**Example 3:**

A 3-ton AC unit requires a starting current of 40 amps and a running current of 19 amps per phase, at 240 volts.

This corresponds to a surge power of 9,600 watts and a rated **power of 4,560 watts.**

A 10,000-watt generator may be able to handle the sustained power demand of the AC unit, but it may struggle to supply enough power to meet the unit’s high starting current demand.

In this case, a generator with a capacity of at least 12,000 watts or higher would be recommended to ensure reliable operation.

Recommended Read: What Size Generator to run a 5-ton Air Conditioner?

## How to Determine the Power Requirements of a 3-Ton AC Unit?

### 1. Calculate the Area to be Cooled:

Measure the length and width of the room or space that needs to be cooled to determine its square footage.

For example, a room that is 20 feet by 30 feet has a square footage of **600 sq. ft.**

### 2. Determining The Cooling Capacity:

Cooling capacity is measured in British Thermal Units (BTUs) per hour. The cooling capacity required for an area depends on the size and location of the space, as well as factors such as insulation, ceiling height, and sun exposure.

A general rule of thumb is that 1 ton of cooling capacity is needed per **500-600 square feet** of living space.

Therefore, a 3-ton AC unit is suitable for an area of about 1,500-1,800 square feet.

### 3. Power Requirement:

The power consumption of an AC unit is measured in watts. To calculate the power consumption of a 3-ton AC unit, multiply the cooling capacity **(in BTUs) by 0.293.**

For example, a 3-ton AC unit with a cooling capacity of 36,000 BTUs per hour will consume approximately 10,548 watts.

### 4. Unit Efficiency:

The efficiency of an AC unit is measured by its Seasonal Energy Efficiency Ratio (SEER).

The higher the SEER rating, the more efficient the unit is. A more efficient unit will consume less power than a less efficient one.

For example, a 3-ton AC unit with a SEER rating of 14 will consume less power than a 3-ton unit with a **SEER rating of 10.**

### 5. Consider the Local Climate:

The climate in the area where the AC unit will be used will affect its power consumption.

In hotter and more humid climates, the AC unit will need to work harder to cool the space, which will increase its power consumption.

In cooler climates, the AC unit will consume less power. For example, an AC unit used in a hot and humid climate like Florida will consume more power than the same unit used in a cooler and drier climate like Colorado.

### How Many Watts Does a 3-ton AC Use?

A 3-ton air conditioning unit typically uses around 10,000 to 12,000 watts (10 to 12 kilowatts) of power per hour of operation.

This power consumption can vary depending on the efficiency of the unit, the climate, and the specific characteristics of the space being cooled.

To determine the exact power consumption of a 3-ton AC, you can calculate it by multiplying the cooling capacity of the unit (measured in British Thermal Units or BTUs per hour) **by 0.293.**

For example, a 3-ton AC unit with a cooling capacity of 36,000 BTUs per hour will consume approximately **10,548 watts of power.**

Recommended Read: What Size Generator to Run a 2-ton AC unit?

## Best Generators for 3 Ton AC Unit

Generator Model | (Starting/ Running) | Fuel Type | Fuel Tank Capacity | Run Time (50% Load) | Noise Level | Weight |

Honda EU7000iS | 7000 / 5500 watts | Gasoline | 5.1 gallons | 6.5 hours | 52-60 dBA | 261 lbs. |

Westinghouse WGen9500DF | 12500 / 8500 watts | Dual Fuel (Gasoline/Propane) | 6.6 gallons | 17.5 hours | 73 dBA | 220 lbs. |

Generac GP15000E | 22500 / 15000 watts | Gasoline | 16 gallons | 10 hours | 78 dBA | 390 lbs. |

Champion 100294 | 9375 / 7500 watts | Dual Fuel (Gasoline/ Propane) | 6 gallons | 8 hours | 74 dBA | 202 lbs. |

Briggs & Stratton 30743 | 8750 / 7000 watts | Gasoline | 7 gallons | 9 hours | 74 dBA | 221 lbs. |

**Frequently Asked Questions (FAQs)**

### What Size Generator Do I Need to Run a 3-Ton AC Unit?

A 3-ton AC unit typically requires a generator with a minimum capacity of 10,000 watts, or 10 kilowatts. However, the exact size of the generator needed may depend on factors such as the starting wattage of the AC unit and other appliances connected to the generator.

### How Do I Determine the Starting Wattage of My AC Unit?

The starting wattage of an AC unit can typically be found on the unit’s nameplate or in the owner’s manual. If this information is not available, you can contact the manufacturer for assistance.

### Are There Any Safety Precautions I Should Take?

It is important to follow all safety guidelines provided by the generator manufacturer, including keeping the generator outdoors in a well-ventilated area, not overloading the generator with too many appliances, and avoiding contact with the generator when it is running.

### What Is the Starting Wattage of a 3-Ton AC Unit?

The starting wattage of a 3-ton AC unit can range from 3,500 to 5,000 watts. It is important to select a generator with a capacity that is greater than the starting wattage of the AC unit to ensure that the generator can handle the initial surge of power required to start the unit.

Fareed, the highly skilled electrical expert, boasts 5 years of extensive experience in proficiently maintaining, repairing, diagnosing, and installing a diverse range of electrical systems.