If you want to run your appliances during a power outage, you need a generator. But if you cannot survive without a hot shower, you should think twice before connecting your water heater to a generator because water heaters use a lot of power.
Can You Run A Hot Water Heater On A Generator?
You can run a water heater on a generator, but only if the generator has a rating that matches that of the water heater. It isn’t enough but the generator’s rating should exceed the rating of the heater and pump. This way, the electrical needs of your appliances can spike without overwhelming the generator.
You need a model that can continuously generate the wattage the water heater requires.
Water heaters are available in various types. The most common is the conventional electric tank water heater. This type of water heater runs on electricity. Once a power outage occurs, it won’t work. Though, if you have hot water in the tank, it will remain warm for a while.
Gas tank water heaters do not rely on electricity. A water heater with a continuous gas pilot light can function without electricity. You can use it in the event of a power outage.
Electric on-demand and gas on-demand water heaters require electricity. You would expect gas on-demand water heaters to run in the absence of electricity. However, they have a control panel that uses electricity. You have other types of water heaters, including solar and heat coils.
But most of the consumers that want to operate their water heater on a generator during a power outage have the conventional electric variety.
The type of water heater matters because gas tankless water heaters use less electricity than their electric counterparts.
A whole-house electric water heater can use as much as 5000 watts. A gas on-demand heater, on the other hand, will only consume 100 watts. Therefore, the type of heater will determine the rating of the generator you will use.
There are some additional requirements that many homeowners forget. They know that the rating of the generator has to match the rating of the water heater.
But they do not realize that the start-up power of a water heater is higher than the ordinary operational power of the appliance. This is especially true in situations where the generator has to operate a submersible pump and the heater.
Running a water heater on a portable generator is more challenging because they do not produce as much power as their permanent counterparts. On occasion, you can find portable generators that can produce as much as 17,500 watts.
But you would be lucky to find a portable generator that can produce 5,000 watts in your local store. Powerful portable generators are expensive. The majority of portable generators in residential settings are not that powerful.
Does your water heater have a power cord? Can you connect it to a regular outlet?
This question matters because a lot of water heaters must be hard-wired. If this is the case for your water heater, you can’t just connect it to the outlet of a portable generator. Keep this in mind before you proceed.
How many appliances do you plan to run on the same generator?
If the water heater is the only appliance on the generator, you can use a generator whose rating matches the water heater.
On the other hand, you need a more powerful generator if you want to run other devices, including freezers, microwaves, and air conditioners.
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What Size Generator Do I Need To Run A Hot Water Heater?
If your water heater uses 4 kilowatts of power, it can run on a generator that produces 5 kilowatts of power. The more powerful the generator, the better, especially if your objective is to run every other appliance in the house.
This makes sense for people whose water heaters are hard-wired. Because you can’t plug the water heater into the generator, you need a whole house generator.
Naturally, the size of the generator has to exceed the total wattage of all the appliances in the house. If you cannot afford a powerful generator, limit the number of devices in use simultaneously.
Do not operate any other appliances when the water heater is running. Of course, it might be easier and cheaper to get a smaller water heater that matches the limitations of the generator.
Some single-element water heaters that require 110/120V can run on generators with a rating of 2500W. As the name suggests, they have one element instead of two.
Keep the cost of running the generator in mind. A conventional generator can consume 25 gallons of gas every day. This estimation applies to a 12000W generator. The more powerful the generator, the more gas it will consume.
You cannot afford to run the generator24/7. Fortunately, no one uses their water heater every hour for the whole day. Most people use their water heaters in bursts ranging from a few minutes to an hour, depending on the number of people in the home.
How Many Watts Does It Take To Run A Hot Water Heater?
Most people use their water heaters for roughly 3 hours each day. On this basis, the average water heater uses 4000 watts.
Energy Use Calculator has a tool that can calculate the cost of running your water heater. But you have to enter the amount of use (in hours) that the heater gets, the wattage of the appliance, and the price of each kilowatt per hour in your area.
Do not take this website’s estimation as the standard. If you want to know the wattage of your heater, look at the nameplate. It will tell you the number of watts the appliance consumes.
How To Connect Hot Water Heater To Generator?
1). Start by matching the water heater to a generator of the correct size.
2). Get a 10/2 AWG 30A cable that is long enough to cross from the water heater to the generator.
3). Create a customized power cable by connecting the 10/2 cable’s wires to the L14-30 plug.
4). Connect one end of the customized power cable to the junction box at the top of the water heater. Run the other end to the generator’s 240V outlet. Secure the cable using the twist lock feature.
5). If you want to use the generator’s 120V outlet (assuming it has one), connect a 12/2 cable to an L5-30 plug to create a customized power cable. One end goes to the junction box on the water heater. The other end enters the 120V outlet on the generator.
If you did not know, ordinary heaters have two heating elements, but they only use one heating element at a time. You can reduce the heater’s power consumption by running the appliance on a 120V circuit. But it will take the heater four times as much time to make the water lukewarm.
How Many Hours Can A Generator Run A Hot Water Heater?
The average water heater runs for three hours each day. With a 5000W water heater, you can expect to spend $781 a year running the heater on a generator for three hours each day.
You can run a water heater on a generator for as many hours as you want.
It is a question of the amount of fuel in the generator. You can run a generator for 24 hours without rest if the need arises. But it depends on the model.