Will A Gas Furnace Work Without Electricity?

A gas furnace is one of the most commonly used heating systems in North America, and it does not require electricity to function. Instead, it runs on natural gas or propane. 

Although a lack of power will force the furnace into its emergency mode, which means that your home will be heated at half capacity until power can be restored.

Will a Gas Furnace Work without Electricity?

If your gas furnace doesn’t have electrical power, it won’t run. While gas furnaces are fueled by gas, some components, including blower motors, circuit boards, and relays, require electricity to operate.

Gas Furnace Components that require electricity

Some of the gas furnace components that require electricity include:

  • Relays – These are electrically powered switches within the system.
  • Circuit boards – They relay information from the thermostat and the furnace. Here is what to do if your furnace control board has no lights.
  • Blower motors – The fans propel heated air into the duct system through power. It pushes waste products from the combustion process and out through the flue.

Gas Pilot Light versus Electric Ignition

Does it make a difference in how your furnace operates? Which of these two options is the best? Or maybe you just want to know if your heat is gas or electric?

For a long time, gas furnaces have traditionally used a pilot light to ignite the flames. This is because that system doesn’t use external electricity. Therefore, it means the fireplace still operates is the power goes out.

However, newer generations of furnaces use electric ignition, which normally requires electricity to start up. In case of a power outage, these fireplaces will work on battery backup, which means you’ll remain warm.

The advantage of electric ignition furnaces is that they save you the cost of running a pilot light 24/7. It can cost you between $8 and $10 per month.

The problem with pilot lights is that they require a small but steady amount of fuel to be consumed to keep the flame burning at all times. Even if your furnace is not in a heating cycle, a small amount of gas is used for the pilot light. This adds up over time to a lot of wasted fuel.

Which is the Best Choice?

Electronic ignitions are great because of the amount of fuel they help you save. However, it’s still important to keep in mind that they can also develop problems. The choice you make should stem from your personal preferences.

If you want to save on fuel, then an electronic ignition is an ideal choice to consider. But if not, then you can go with a gas pilot light.

What Happens to Furnace when Power Goes Out?

When the power goes out, your gas furnace simply won’t work. This is mainly because the built-in safety system of the gas furnace doesn’t allow it to turn on during a power outage. Another thing you shouldn’t do is try to rig the furnace for heating when the power goes out. 

Doing that can compromise the health and safety of your home. The best option is to wait for power to come back.

Can You Run a Gas Furnace During Power Outage?

For most homeowners that use a furnace with natural gas for heat, having an electrical outage means the furnace will not work. That’s because the furnace’s safety system won’t allow it to turn on during a power outage. 

This means that you cannot run a gas furnace during a power outage. And it’s also not a good idea to try and rig the furnace for heating to avoid compromising your health and safety.

During a power outage, what you need to do is turn off the power to the furnace. This will prevent any damages that may occur when electricity is restored to your home.

How to Run Furnace when Power is Out

The best way to run a furnace when power is out is by using a generator. However, if you want to do that, it’s highly recommended to hire a professional HVAC technician to come and connect the furnace to the generator.

This will allow the furnace to operate from the power of the generator. The good news is that you don’t need a large generator for this. You can just buy a portable one and connect to one or two appliances in your home during a power outage.

Do I Need to Turn Off Gas when Power Goes Out?

Surprisingly, you don’t need to turn off your gas source when the power goes out because it may still be used to power some of your other home appliances. But you have the option of unplugging bigger power users in your home if you want. These may include your television, computers, and any other appliances.

Do You Have to Relight the Furnace after a Power Outage?

No, it’s not safe to relight the furnace after a power outage. That is because the furnace will sense when there is no power, and the gas valve will close. 

This will cut off the flow of the gas and prevent the furnace from functioning. Therefore, this is a safety feature you need to appreciate and avoid tampering with it.

Furnace Safety During a Power Outage

The best furnace safety tip during a power outage is to allow the furnace’s built-in system to shut itself off. You shouldn’t try to rig the furnace because you might put your entire house at risk by doing that.

One thing you have to remember is that a furnace won’t work without electricity. Therefore, it’s designed to sense when electricity is off and shut itself off. 

If you want to continue staying warm after a power outage, then consider connecting a generator to light up the furnace again.

Electric vs. Gas Furnace

One thing you need to know is that both gas and electric furnaces work using a forced heating system. A crucial piece of equipment you’ll find in both furnaces is the thermostat. 

When the room temperature falls below the heat set point on the thermostat, a signal is sent to the furnace unit.

In a gas unit, a signal will cause the pilot light to ignite the main burner of the heat exchanger. The heat exchanger will then draw heat from the main burner and heat the air, which will circulate to the house. 

In an electric furnace, an electric ignition receives the thermostat signal and then activates the heating elements inside the furnace.

In both types of furnaces, heated air is forced by a blower fan through the ductwork in various heated rooms of the house. 


When it comes to installation, a gas furnace is a bit difficult to install compared to an electric furnace. However, the high voltage required by the electric furnace is the main reason you need to consider hiring a professional to install it.


In terms of efficiency, an electric furnace is more efficient than a gas furnace. This is mainly because it may have an annual fuel utilization (AFUE) rating as high as 100%. This is higher than gas furnace ratings which are usually between 55 and 97 percent.


Cost-wise, electric furnaces are normally less expensive than gas furnaces. They are also cheaper to install. A new electric furnace can cost between $1,000 and $2,500, while a gas furnace can cost between $3,000 and $4,000.

The average cost of installing an electric furnace is between $1,000 and $1,500, while that of installing a gas furnace is between $1,500 and $2,000. Therefore, this makes the total cost of an electric furnace between $2,000 and $4,000, while the total cost of a gas furnace is between $4,000 and $6,000.

Maintenance & Safety

An electric furnace is easier to maintain than a gas furnace. That’s because there isn’t any burner to clean or inspect.

A gas furnace, on the other hand, requires regular maintenance by an HVAC professional to ensure it remains efficient and safe. 

Durability & Noise

Gas furnaces usually last for about 10 to 20 years, while electric furnaces can last up to 30 years. Therefore, this shows that electric furnaces are more durable than gas furnaces. 

When it comes to noise, electric furnaces are normally quieter than gas furnaces. This is due to their simple design, and they also tend to have fewer parts moving. 

Electric furnaces also don’t have vents and a burner. Gas furnaces tend to make a loud rushing sound at the time they start running and when the burner ignites. 

How Can I Heat My House without Electricity?

Here are 3 recommended ways you can heat your house without electricity:

  • Use a kerosene heater – Kerosene is a traditional fuel used for heating. It serves as a suitable alternative for heating your home when there is no electricity. However, ensure you use a smaller radiant heater designed for indoor spaces.
  • Set up a wood stove by the window – If you happen to have wood and there is no electricity, then consider setting up a wood stove by the window. But don’t forget to construct a pipe chimney to channel all the smoke out.
  • Create a candle heater – The third option is to build a candle heater. Although candles are not the best sources of heat, you can still use them if you don’t have any other option. 

Does Natural Gas Heat Work During Power Outage?

No, natural gas heat won’t work during a power outage. That’s mainly because the furnace’s built-in safety system will not allow it to turn on during an electrical outage. 

Will a Propane Furnace Work without Electricity?

Yes, most natural and propane gas fireplaces work without electricity and can be good sources of supplemental heat. 

Also, many of them come with built-in, remote, or wall-mounted thermostat options. But you should avoid tampering with your furnace in order to stay safe.