What can you power with a 4000-watt generator?
In order to figure out how much power you’ll be drawing from your 4000-watt generator, you need to add up the wattages of all the appliances you plan to plug into it. However, there’s a catch because any appliances that are driven by a motor – such as your refrigerator, freezer, and air conditioning unit – have two different wattage requirements: running wattage and surge wattage. Running wattage describes how many watts the appliance uses to keep running once it has already started. Surge wattage is typically higher, and is sometimes much higher, and describes the amount of wattage the appliance uses for the few seconds when the motor is starting up.
Thus, you need to make sure that the sum of all the running wattages of the appliances you want to power with your 4000-watt generator is less than 4000 watts, while the sum of all the surge wattages plus the running wattages of non-motorized appliances is less than the surge wattage that your generator is rated for.
To give an example of what a 4000-watt generator is capable of powering, let’s look at some of the common appliances found in a house or RV. 4000 watts give you enough power to run a refrigerator and freezer, microwave, and air conditioning unit, with just a few hundred watts left over for turning on lights and charging small electronics. However, beware that the surge wattage to run these appliances is closer to 5000 watts because they are driven by motors.
Important features to consider before you buy a 4000-watt generator
In order to choose the best 4000-watt generator for your needs, there are a variety of important features on generators that you need to understand because they affect how the generator will work under different circumstances. In this section, we’ll explain these features, what they mean, and how they can impact your purchasing decision.
Rated and maximum power output
All modern generators have two different power outputs – their rated power and their maximum output, or surge, power. The rated power describes the amount of wattage that the generator is able to consistently put out for as long as it has fuel and is the wattage that you cannot exceed once you have all your appliances up and running. For non-motorized appliances, like light bulbs, dishwashers, and even microwaves, the running wattage is the only wattage that matters and you can determine how much wattage your appliances will need simply by adding up all of their individual running wattages.
Note that all of the 4000-watt generators we reviewed actually have rated wattages under 4000 watts.
Maximum power output comes into play when you are powering motorized appliances like refrigerators, freezers, air conditioning units, and some types of pumps. When these appliances are first plugged into the generator, the motor requires a much larger power draw to start up than it does to run once it has started. The maximum power output on your generator will be able to handle this extra wattage requirement for a few seconds, long enough to start these appliances. If you have left yourself leeway when calculating your running power requirement, your generator will likely provide enough surge power to get all your appliances started as well.
The engine is the heart of your generator as it is the component of the generator that converts fuel – either gasoline or propane – into electrical energy. In general, a more powerful engine will produce more power, so that generators that offer roughly equivalent output wattages have similarly sized engines – this is why most of the 4000-watt generators we reviewed have 212cc or 224cc engines.
Fuel tank capacity
All of the 4000-watt generators we reviewed run solely on gasoline, which means that have an internal fuel tank to hold the gasoline. The fuel tank size on these generators does not vary by much and is typically 3.4 to 4 gallons. However, the Westinghouse iPro4200 has a small 2.6-gallon tank, which reduces the overall size of the generator but also reduces the runtime and requires you to refill the fuel tank more frequently. In general, a larger fuel tank will increase the runtime – although this also depends on fuel efficiency – and increase the size of the generator.
The runtime of a generator is typically measured at half-load (i.e. when the generator is running at half its rated wattage) and is a measurement of how long the generator can run on a single tank of fuel. The runtime depends on both the size of the fuel tank and the efficiency of the generator’s motor. Generator runtimes on 4000-watt units range from just eight hours at half load on the DuroStar generator to an impressive 18 hours at half load on the Westinghouse iGen4500.
Note that the generator’s fuel efficiency depends in large part on how much wattage is being drawn from it. For a single generator, the runtime will be shorter when running it at maximum capacity compared to running it with only a single appliance plugged in.
The number and type of outlets found on your generator are extremely important since it determines what types of appliances and how many appliances you can plug in without having to resort to power strips and electrical adapters. The number of standard 120V outlets can range from just two, like on the DuroStar and Pulsar generators, to as many as six on the Westinghouse iPro4200 generator. If you plan to use your generator to power heavy tools, it is important to look for a unit that offers a 120V/240V 30A twist-lock outlet. On the other hand, if you want to use your generator to power an RV, an RV-ready 120V outlet like the kind found on the Wen generators may be the most important outlet to have. In addition, some generators like the Westinghouse models and the Pulsar generator offer USB ports for charging small electronics. Another outlet that can be extremely useful is a 12V DC outlet, like that on the Champion generator, that can be used to charge a battery for your car, RV, or boat.
Although you may be focused in on power when looking at generators, it’s also important to consider how much noise a generator will make once it is started up. Noise is a particularly important concern if you plan to use your generator for an RV or camping. The noise of a loud generator can wake up an entire campsite or prevent you from falling asleep. Even for home use, a loud generator can keep you or your neighbors up at night and generate complaints.
In general, generators with larger engines will produce more noise, although the amount of noise reduction built in by the manufacturer can also play a large role in noise. For example, the Westinghouse generators produce only 52 dB of noise while the similarly powerful DuroStar and XtremepowerUS 4000-Watt Gasoline Generator generators produce 67-69 dB of noise.
Size, weight, and portability
The size, weight, and portability of different generator models can matter more or less depending on where you plan to keep it and how you plan to use it. For occasional household use where the generator sits in the same place where you expect to use it, portability may be a non-issue. On the other hand, if you plan to use your generator with an RV for camping, having an enormous and heavy generator can be problematic. Thankfully, although 4000-watt generators are heavy to carry by yourself, most are manageable in size compared to larger generators. If portability is a serious concern, the Wen, Pulsar, and Westinghouse iGen4500 generators are mounted on a set of wheels to make them easier to move around.
A 4000-watt generator is a significant investment so you want to be sure that your generator will work like new for many years to come. A manufacturer’s warranty can protect your purchase in case anything goes wrong with your generator and helps to provide peace of mind for your purchase. Warranties vary in length from just one year on the DuroStar unit to up to three years on all of the Westinghouse and Champion generators.
How much should you expect a 4000-watt generator to set you back? These units range widely in cost, but you should expect to pay at least several hundred dollars to get a reliable unit. Our budget pick, the DuroStar generator, costs just over $250, while the Pulsar and Westinghouse iGen4500 models run for $850 and $950, respectively.
When looking at generators, opt for the most reliable model that has the surge power and features you need – it’s better to pay a little extra now than have to buy a new generator in a few years.
Once you have your new generator in hand, how do you hook it up? Here are some of our favorite tips to help you get started with your generator.
- For safety reasons, never operate the generator inside or in enclosed areas.
- Plug appliances into the generator rather than trying to backfeed electricity directly into your home’s electrical grid – it’s illegal!
- Always allow the generator to cool down completely before adding more fuel to the reservoir.
- Keep enough motor oil and filters on hand – in addition to gasoline – to get you through an extended power outage.
- Don’t allow the generator to fully run out of gas, as this can damage the engine.
- Never leave gas in the generator after you’re done using it as it can go stale and cause engine damage the next time you start it up.