How big of a generator do I need to run a 5,000 BTU air conditioner? (Can your generator run it)

When using a generator to power a 5,000 BTU air conditioner, be sure to know the unit’s size and wattage specifications, consider usage duration for runtime and fuel needs, and account for climate conditions.

Navigating the need: Generators for air conditioners in diverse situations 

You might need a generator for your air conditioner in various scenarios, such as power outages, camping trips, or emergencies. In moments like these you need a stable and reliable power source.

From handling unpredictable events to enhancing camping experiences and ensuring emergency preparedness, a generator serves as a versatile solution for continuous and reliable power for your air conditioning needs.

The most important thing when it comes to generators is determining the appropriate size for your specific air conditioner.

For a 5,000 BTU air conditioner, assessing the generator’s capacity involves considering factors like the start-up wattage surge, operational efficiency, and the overall power requirements of the air conditioner.

Choosing the right generator size for your 5,000 BTU air conditioner: A comprehensive guide

To establish the required generator size, take into account both the starting wattage (higher during the initial compressor kick-in) and the running wattage (continuous power to keep the unit running).

Refer to the air conditioner’s manual or specification sheet to find information on both the starting wattage and running wattage.

Then, add a safety margin of around 20% to ensure the generator has enough capacity to handle fluctuations and additional loads.

As an example, if the starting wattage of your 5,000 BTU air conditioner is 1,200 watts and the running wattage is 500 watts, you would want a generator with a capacity of at least 1,200 watts (or higher).

If you don’t know the starting wattage and running wattage, then an approximation can still be made:

The wattage (W) of an air conditioner can be calculated using the formula:


Your AC Wattage = 5,000 x 0.293 = 1,465 Watts

The Energy Efficiency Ratio (EER) is a measure of how efficiently an air conditioner uses electricity, and can be calculated using the formula:

For example, for the 1,465 Watts above, the EER of such an air conditioner of 5,000 BTU would be 3.4:

5,000 BTU/h / 1,465 Watt/h = 3.4 EER

To get the wattage of your air conditioner, use this formula:

Example 1: 5,000 BTU / 7 = 714 Watts, then you need an 800-watt generator and above.

Example 2: 5,000 BTU / 12 = 417 Watts, then you need a 500-watt generator and above.

Below we have calculated the generator recommended size, based on different EER for a 5,000 BTU air conditioner:

EER How many watts of generator needed Available on Amazon
7 800-watt generator and above AIVOLT Portable Power Station 800W
8 700-watt generator and above ALLPOWERS S700 Portable Power Station 700W
9 600-watt generator and above OUPES 600W Portable Power Station
10 600-watt generator and above ENERNOVA ETA Portable Power Station 600W
11 600-watt generator and above Kingboss Portable Generator 600W
12 600-watt generator and above Tiexei Portable Power Station 600W

This is in theory only. This table is to give you an idea of how a 5,000 BTU air conditioner wattage is computed with regards to the unit’s EER.

Always refer to the specific EER rating of your air conditioner and consider both starting and running wattage when selecting a generator to ensure efficient and reliable operation.

How to pick the right generator to run perfectly on a 5,000 BTU AC?

A 5,000 BTU air conditioner is the preferred size for frequent campers due to its compact and easy-to-handle nature.

With a substantial number of people engaging in outdoor activities, the importance of portable generators and air conditioners in providing comfort has become crucial for ensuring this comfort off the grid.

When choosing a generator whether for camping, RV use, or home power outages, besides your budget and customer reviews, there are several other factors to consider to ensure you select the most suitable option for your needs:

1. Power requirements:

Consider both the starting (surge) and running (continuous) wattage of each appliance you intend to use to prevent overloading the generator.

2. Fuel type

Generators commonly use gasoline, propane, or diesel. Select a fuel type that is readily available and convenient for your usage:

Fuel type Characteristics
  • More affordable and widely available.
  • Limited shelf life, requires stabilizers for long-term storage.
  • Emits fewer emissions than gasoline.
  • Indefinite shelf life, suitable for long-term storage.
  • Slightly higher initial cost for propane generators.
  • Suitable for heavy loads and extended runtimes.
  • Longer shelf life compared to gasoline.
  • Higher initial costs and less readily available fuel compared to gasoline.

3. Runtime and fuel efficiency

Consider the generator’s runtime on a full tank of fuel. Opt for a model with sufficient runtime for your needs.

4. Climate considerations

In diverse climates, the effectiveness of generators and air conditioners is influenced by environmental conditions. Tailor your approach based on the climate.

Climate Recommendations
Cold Climate
  • Use winter-grade fuel or a stabilizer to prevent fuel gelling.
  • Keep the generator sheltered to protect it from snow and ice.
Hot Climate
  • Ventilate the generator to prevent overheating.
  • Regularly inspect oil and coolant levels.
Humid Climate
  • Place the generator in a dry, well-ventilated area.
  • Regularly inspect and clean the generator to prevent corrosion.

5. Portability:

Opt for a portable and lightweight generator, with features like wheels and handles for easier transportation:

Feature Benefits and Considerations
Portability Valuable for outdoor activities, camping trips, and emergencies where mobility is crucial.
Weight considerations Choosing a lightweight model ensures easy transportation without excessive effort.
Wheels Generators with wheels are useful for navigating uneven surfaces or covering longer distances.
Handles for lifting Integrated handles facilitate easy lifting and carrying, enhancing overall transportation convenience.
Compact storage Portable generators with compact designs are easier to stow away in storage spaces without taking up excessive room when not in use.
User-friendly design Intuitive controls, easy-access maintenance points, and clear instructions contribute to a positive user experience, making operation more convenient.

6. Noise level:

Check the noise level of the generator, especially if you plan to use it in campsites or residential areas. Inverter generators are generally quieter than conventional ones.

7. Safety features:

When selecting a generator, it’s crucial to prioritize safety features to safeguard both your connected devices and the generator itself. Here are key safety features to look for:

Safety feature Benefits and considerations
Overload Protection
  • Ensures generator longevity.
  • Protects appliances and electronics from potential damage due to excessive power demand.
Low Oil Shutoff
  • Critical safety measure.
  • Automatically shuts down the generator when oil level falls below a safe threshold.
  • Prevents engine damage and minimizes the risk of malfunctions.
Automatic Voltage Regulation (AVR)
  • Maintains steady voltage.
  • Protects sensitive electronics from harmful voltage fluctuations.
Ground Fault Circuit Interrupter
  • Important for outdoor or wet conditions.
  • Enhances electrical safety by minimizing the risk of electric shock.
Circuit Breakers
  • Additional protection for both generator and connected devices. Resettable circuit breakers allow quick restoration after tripping.
Carbon Monoxide (CO) Detection
  • Automatic shutdown feature for models with CO detection.
  • Crucial for preventing carbon monoxide exposure.
  • Especially important in enclosed or indoor spaces.

8. Emissions and compliance:

Check the generator’s emissions rating and ensure it complies with local regulations, as some areas have specific requirements for environmental standards.

Additionally, before finalizing your purchase decision, we advise checking the warranty terms and coverage, as well as ensuring the availability of customer support and service centers for the selected brand.

Powerful versatility: Choosing the right generator for multiple appliances

If you plan to power additional appliances along with your air conditioner, we recommend opting for a higher-wattage generator.

A generator ranging from 2,500 to 3,500 watts is generally sufficient to simultaneously operate your air conditioner, TV, appliances, and charge your devices effectively all at the same time.

This Generac 7127 iQ3500 is a 3,500 watt gas-powered portable inverter generator designed for versatile power on the go, suitable for camping trips, home power outages, and more.

Its durable yet lightweight construction ensures easy portability, catering to a range of situations.

The generator offers the flexibility of choosing between two engine speeds based on your requirements, allowing you to minimize noise and fuel consumption or maximize power response.

Buy it on Amazon

Using a 8,000 BTU AC? Check this article: How big of a generator do I need to run a 8,000 BTU air conditioner? (Is your generator capable of running AC)

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