How Many Amps Does a Space Heater Use? (Explained)

If you live in areas like Alaska, Minnesota, Wisconsin, and Wyoming, you will be hard-pressed not to own any HVAC unit that dispels warm air. Space heaters are often the go-to option for homeowners with large or small rooms that need additional warmth. 

For those who don’t own this device yet, but are interested in investing in one, a good question to ask is how many amps does a space heater use? And if you already have yours installed, you would also be curious about its energy consumption. You are in the right place because this blog post will explore the electrical rating measured in amps for space heaters of different variations. 

How Many Amps Does a 5000-Watt Heater Draw? 

A 5000-watt space heater draws between 20 to 42 amps of electrical currents for each hour it is plugged in. Typically, these devices use a volt rating of 120 or 240 volts, and that will ultimately determine the energy consumption. 

A 5000-watt space heater with a 120-volt rating draws 41.7 amps hourly. On the other hand, 240-volt heaters will use 20.8 amps every hour that they are plugged in. 

But of course, a 5000-watt space heater is a large HVAC unit often used for garages and spacious rooms. They will provide too much heat for smaller spaces. 

5000-watt space heater consumes a high amount of thermal energy. This is why the amperage rating is high, regardless of the volts it uses. It will take a lot of electricity to convert the cold air in the room to heat energy. 

Space heaters are built with a heating mechanism that requires high energy, placing them among the highest electricity consumers among household appliances. 

Aside from your willingness to dedicate a significant electricity consumption to your 5000-watt space heater, you must also prepare an adequate surge protector for your appliance. 

If it draws 20.8 amps, an allowance of an additional five to six amps should be considered when choosing a dedicated circuit. Your best bet is a 30-amp breaker for this device type. 

How Many Amps Does a 2000-Watt Heater Draw? 

A 2000-watt heater draws 16.7 amps if it has a 120-volt rating, while a 240-volt device consumes 8.3 amps. This is easily calculated by dividing the wattage number by the volts it uses. 

2000-watt heaters are more suitable for smaller to medium-sized rooms of about 150 square feet. These space heaters will consume less electricity because they are smaller, but they are still among the higher energy consumers than other household appliances. 

Several factors affect the amp rating of an electrical appliance, including the heating speed. For this reason, your 2000-watt space heater will consume more electricity if you set it to a high speed, but when kept on low, it will require less. 

To protect your investment, you may need a surge protector. But you cannot use just any breaker because there are rules about how much allowance to provide to avoid defeating the purpose. 

For a 2000-watt space heater, opt for a 15-amp circuit breaker when your device uses 240 volts. On the other hand, a 20-amp breaker will suffice for a space heater that uses 120 volts. 

How Many Amps Does a 1500-Watt Heater Draw? 

A 1500-watt space heater draws 12.5 amps of energy when equipped with 120 volts, and 6.3 amps will be drawn hourly when dealing with a 240-volt space heater. 

There is little difference between the capacity of a 2000-watt space heater and one with 1500-watt energy consumption. They are suitable for small to medium spaces of 150 feet or thereabout. 

As with other household appliances, your 1500-watt heater can also be manufactured with a 120-volt rating or 240 volts. 

When choosing a space heater of this size and capacity, the better option is an infrared heater because it heats objects within its designated range instead of warming the air. This is considered more energy friendly because it hits its mark. 

And since the people and objects in the room experience the warmth directly, it is more effective. 

It is also worth knowing that the process of heating the room and atmosphere (convection or infrared) determines the energy consumption. 

Heat transfer through convection occurs by an internal heating element that uses fluids plus thermal energy. The process of heating the liquids consumes power. 

In contrast, infrared heating sends warmth straight to objects and humans. It needs no additional heat creation or transfer, cutting down on electrical currents drawn. 


How Many Amps Does a 750-Watt Heater Draw? 

If the 750-watt space heater has been designed to draw 750 watts at a voltage of 120v, it will use 6.25 amps. On the other hand, wired to rely on 240v, it will consume 3.1 amps of energy. 

There are 750-watt space heaters, and you can easily deduce that they are small and hereby designed for smaller spaces. Perhaps a single person’s room. 

These portable devices can also be moved around from one room to another. However, that is not the only benefit. 

A 750-watt space heater also uses less energy to warm the room. But, of course, it will not be as efficient as a larger model. 

How Many Amps Does a Space Heater Use on Low? 

On low, a space heater uses half of its usual amperage consumption. This means that if yours is a 2000-watt space heater, it will use 1000 watts. If it is 750 watts, it consumes 375 watts. In amps, that is 8.3 and 3.1 amps, respectively. 

Putting your space heater on low after it has worked for a while will help you reduce your power consumption. You can also do this to avoid leaving it on all night. 

If you aim to heat your room more effectively without consuming too much electricity, go for a radiant or infrared space heater instead of one that adopts the convection method. 

That way, it will direct the heat to objects in the room instead of the air. Heating the air is less effective because it relies on an additional HVAC source (like a ceiling fan!) to circulate the hot air around the room. 

On low, you will be able to conserve even more energy. 

Why Would a Space Heater Trip the Breaker? 

A space heater would trip a breaker if there is an electrical overload or too many devices are plugged into the circuit. Your circuit breaker may also be past its prime and, therefore, incapable of handling the load it was designed to handle. 

Circuit breakers have been designed to control the energy appliances receive. But they have limitations, measured in amps or amperage. 

You will often find 15 or 20-amp circuit breakers in most homes, and the energy each outlet can dispense is limited based on the circuit breaker you plug in. Luckily, various options are not restricted to 15 or 20 amps. 

There is one caveat, however. It is a rule of thumb to avoid plugging devices whose total amperage power exceeds eighty percent of the circuit breaker’s capacity. 

In other words, keep the appliances within eighty percent of the circuit breaker’s capacity to avoid tripping it. 

That being said, your space heater will trip the breaker if you plug it (a 2000-watt heater) into a 15-amp circuit breaker. It will cause an overload, which can happen when you connect a 750-watt heater and other appliances exceeding 12 amps into a 15-amp circuit breaker. 

Remember to keep it within eighty percent. 

Another reason is that the circuit breaker may be worn out. If your space heater keeps tripping the breaker, you may be plugging it into a socket past its prime. This is dangerous, and you need an electrician. 

Can I Use a Surge Protector With a Space Heater? 

Yes – if your home experiences electrical spikes or any inconsistency in the electricity supply, like flickering lights. A surge protector will protect the unit and outlet of areas you plug it into. 

But again, surge protectors can be limited in their power capacity, so you must be careful when using them with a space heater. 

With a space heater, especially if it is one of those models that draw 2000 watts upwards, look for surge protectors that accommodate at least 120 percent of the heater’s amperage consumption. The reason is that the power capacity of surge protectors is often limited to 15 amps, but you can look for higher capacities. 

A surge protector does a great deal in protecting household appliances, and you should take advantage of one. But if you don’t experience any electrical variation, you can ditch a surge protector. 

Do Space Heaters Need a Dedicated Circuit? 

Yes, space heaters (especially those consuming above 1500 watts) need a dedicated circuit. According to the National Electrical Code, major appliances need one, and a space heater falls into this category. 

Space heaters consume a significant amount of energy. So, they need a dedicated circuit that can manage the inflow of the currents without succumbing to an overload. It also regulates the power that flows into the space heater. 

Can You Run a Space Heater on a 15 Amp Circuit?

Yes, you can run a space heater on a 15-amp circuit. However, ensure the space heater’s amp consumption is at most eighty percent of the circuit’s capacity. 

If your space heater consumes 5000 watts, you cannot run it on a 15-amp circuit breaker. Look for a more power-compatible fit instead.


A space heater for a small room consumes fewer amps. But a larger device requires more energy and will therefore have a higher amperage rating. 

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About Rinkesh

A true environmentalist by heart ❤️. Founded Conserve Energy Future with the sole motto of providing helpful information related to our rapidly depleting environment. Unless you strongly believe in Elon Musk‘s idea of making Mars as another habitable planet, do remember that there really is no 'Planet B' in this whole universe.