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How Much Gas Does a Boiler Use? (Quick Answers)

Whether it is the cold days or the warm ones, a broiler is more or less used in every kitchen. But not all of us notice how much energy a broiler uses. However, it affects the utility bill that you pay every month.

Therefore, it can be considered productive to check how much gas your broiler uses for both the environment and your pocket. As we often have multiple questions regarding this, we will try to break things down for you today.

How much gas does a boiler use?

The exact figure of how much gas a broiler uses varies; check the value determined (24-27 kW, 30-35kw) by the manufacturer is the amount of gas or energy a boiler can use in an hour. Therefore, if you’re using a 25-kilowatt combi boiler, it can use up to 25-Kilowatt energy in an hour. 

In most houses of the U.S.A water heaters or boilers are used as a source of hot water or steam. Boilers consume some amount of energy in order to heat up the water.

The steam is then divided into pipes through a radiator. And in the case of hot water, it is distributed through underfloor heating systems or baseboard radiators. 


Combi boiler:

Combi boilers are the most commonly used boilers. This type of boiler consumes comparatively less space in your house.

The boiler supplies hot water to all the taps without the need of storing the water. If a combi boiler is of 27kWh, then per hour it will consume up to 27 kWh energy.

The best part about combi boilers is they are up to 90% effective. In comparison with conventional boilers, combi boilers have a minute carbon footprint.

In case you’re wondering if old boilers are likely to use more gas, then let us inform you that they do. However, upgrading to a brand-new combi boiler can help you save around 25-40℅ on your bills.

LPG boiler:

LPG boilers use LPG to produce the energy needed to heat your water. LPG boilers usually consist of a storage tank and boiler. The best part about LPG boilers is that it produces around 18-20% less carbon.

LPG boilers are highly efficient, compact in size, and comparatively quieter than other gas boilers.

LPG gas boilers can be considered up to 50% less costly than natural gas using boilers. Therefore, it can be considered that it uses much less gas per hour in comparison to combi boilers.

Using an old boiler will have some impact on your bills. Whereas getting a new boiler can be proven pocket-friendly.  

On average, these boilers are almost 88-92℅ efficient. They are a great option if you plan on investing in a boiler.  


30kw boiler:

A 30kw boiler is a boiler that will use up to 30 kW of energy per hour. In the case of a 30-kW combi boiler, you can run up to 12-15 radiators.

35kw boiler:

In terms of a 35kW boiler, 35-40 kW boilers are preferable for large-sized houses. 35kW combi boilers tend to use 35kW of energy per hour. A boiler of this size is more than enough to run and heat up to 15-20 radiators. 

Does the boiler use less gas? Are gas boilers expensive to run?

A new boiler will use up to 43-45% less energy to produce the same heat as the new one.

Gas boilers are usually less expensive to use. Per kWh, gas can be almost four-five times less than electricity. Electronic boilers are compact, have affordable installation costs, and are more efficient. A standard electric boiler can cost up to three times more than a gas boiler. 

Whereas gas boilers are cheaper to run. They can be proven highly budget-friendly. So, natural gas is significantly more affordable than electricity.

If you live somewhere cold and need to use the heater almost throughout the year, then a gas boiler is a better option. They heat up fast and produce maximum heat in no time. It will help you save money in the long run.  

As gas boilers run on combustible fuel, they need to be maintained often. Regular maintenance ensures smooth operation and ensures safety.   

How much gas does a boiler pilot light use?

Using a standard pilot light for an hour can consume 0.579 cubic feet and 13.90 cubic feet of gas per day.

Pilot light is a comparatively small flame that is designed to burn continuously. In case you’re wondering why to let us explain.

The pilot light is used to light up the main burner of the boiler when you turn it on. As the pilot light burns all the time, it consumes a certain amount of gas. According to a study, using a pilot light can cost up to 110-115$ a year.

Boilers that age around 15 years or more do not come with pilot lights. However, they have an electronic ignition feature that helps the boiler light up.  

If your old boiler comes with a pilot light, you can look for another energy-efficient substitute.

Regular maintenance will resist your boiler from using more gas and keep your bills down. This can help you save some money. If you plan to keep your bills reasonable, it’s always better to switch to an efficient option.  

How much does it cost to run a gas boiler per hour?

To run a gas boiler per hour costs around $0.43-$0.51.

Every fuel or gas has its own cost. The cost of gas may differ due to the size and age of the boiler. Also, the fuel you are using to heat your boiler can create a difference.

For the electricity rate by kWh, it costs around 12.52 cents. It is better to remember that the cost can vary due to usage. On cold days, heat loss is more, so it will cost more.

A 24 kWh boiler uses 24 kWh of energy each hour. In case if you run your boiler for six hours, then 24×6 = 144 kWh. Each hour costs 0.43 cents, therefore, 6×0.43= 2.58 USD. This is the cost of gas to run your boiler per day.

How do I calculate boiler fuel/gas consumption?

Boilers consume gas depending on their output. Propane and natural gas have different energy levels. However, you should know that gas boilers are not a hundred percent efficient.

Therefore, if you know the efficiency rate, then the exact fuel consumption can be calculated. The calculation process isn’t the same as the gases have various energy levels.

Below are a few steps you can use for the approximate Gas consumption calculation: 

Checking the burner output rating:

The burner output rating can be found on the appliance sticker or the user documents.

Determining fuel and conversion factors:

The next thing you would need to do is figure out the conversion factor of the gas you’re using. When the burner turns gas into heat energy, the burner loses some energy.

Dividing the BTU with conversion term:

The approximate conversion factor can be then divided by the BTU output. Each natural gas burner uses an amount of 40,000 BTUs/ hour.

How to use a gas boiler efficiently?

When you use your boiler efficiently, certain facts can have an impact on the usage of gas. Here are a few things you can follow to improve the efficiency of the boiler:

Proper maintenance:

Proper maintenance is the first and foremost thing you can do to resist any inconvenient breakdowns. This includes inspecting pipes, lubricating parts, checking the water level, etc. 

Some extra air in the combustion chamber of a boiler consumes energy from gas. Although gas boilers need a certain amount of air, excessive air can turn into disastrous fuel gases.

Monitoring the system:

Monitoring the system can help in ensuring that everything is working properly. You may look for leaks or check the water level every 14-15 days.

Replacing thermostat:

Another thing you might want to do for increasing efficiency is to replace your old thermostat. Investing in a new programmable thermostat will give you better performance.

If the thermostat is installed properly, the boiler will consume comparatively less energy. However, the boiler will help you stay comfortable throughout the year.

Using ceiling fans:

During the winter, try using your ceiling fan. You can reverse the direction if you flip the button on the top of the fan. As the blades run in reverse, the warm air near the ceiling gets pushed out. This helps the warm air to get out inside the room.

This will have an impact on the usage of gas consumption even in a low thermostat.  

Final Thoughts

In the case of combi boilers, the amount of kWh mentioned in the manufacturing details is the amount of energy they consume each hour. On the other hand, in the case of gas boilers are highly efficient. However, the amount of gas consumption may vary due to different reasons.