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

If you suddenly notice an increase in your utility bill, you may want to keep an eye out for the boil. During the colder months, it is normal for your boiler to run more and hence consume more gas.

Nonetheless, knowing how much gas your boiler is using can help you cut the costs. There’s no point paying more than you’d need to!

Boiler gas usage

On average, a 24-kW power boiler will consume 2w kWh of gas, The amount of gas that a boiler will use would depend on a few deciding factors. This includes the type and size of the boiler, usage, and consumption, condition of the boiler, and the heating area.

Different types of boilers use different amounts of gas. Let’s get to know more about them.

Combi boiler: 

As the name suggests, a combi boiler is a combination of an electric one and a normal one.

This means that the difference between the two is that combi boilers heat water from the source instead of needing a separate cold-water tank. Not only does this save space, but combi boilers are also said to be more economical.

These boilers require about 20 to 30% less gas. When compared to conventional boilers, combi boilers are also said to be more efficient. However, these boilers have to be serviced regularly.

LPG boiler:

LPG boilers are different from combi boilers or normal ones as they use liquid petroleum to provide the energy required to heat the water.

LPG boilers have several advantages over normal ones and one of them is fuel efficiency.

Because these types of boilers are considered to be 50% more gas effective, LPG boilers could decrease your gas bills to half of what is incurred with the normal boilers.

 Not only that, LPG boilers are space saving and less noisy than the normal ones.

How much gas does a 30kw boiler use per hour?

The math is simple when it comes to how much gas a boiler of a certain power uses in one hour. If you have a 30-kW boiler, in one hour, that boiler will use 30kwH of gas.

Kilowatt hours or kWh is a measure of the energy and precisely shows how much gas or energy any appliance will consume for the time it is turned on.

How much natural gas does a boiler use?

Generally, a boiler in working condition can use 24kW energy in one hour. So, if you wish to estimate a boiler that has been turned on for 3 hours, the boiler would use 72 kWh of natural gas.

However, an old gas that has broken thermostat or control valves may consume a lot more. Additionally, if the house is not well insulated, the boiler will consume more.

Why is my boiler using so much gas?

There are one or more reasons why your boiler has been using so much gas. Here are a few possibilities that you may look into:

Your boiler is too old:

On paper, it is recommended that one change their boiler to get a new one, every 10 years. This is because, after 10 years of usage, a boiler’s efficiency drastically drops.

When the boiler is new, it may operate at proficiency of 80 to 90 percent whereas older ones would barely work at 30 percent. It has been observed that old boilers may consume about 10 to 15 kWh more than a new boiler.

A faulty thermostat or programmer:

A thermostat is what controls or programs the boiler for how long it would be turned on or when it would be turned off.

When the thermostat or programmer starts to act up, your boiler may be running for more hours and using up more gas. Hence you may want to run checks now and then to see if the time and temperature settings are as they should be.

Motorized valve is broken:

When hot water flows from the radiator to the boiler, the speed and volume of the water are regulated by a motorized valve.

If this valve becomes out of order and allows too much hot water to flow through for too long, your boiler will use up excess gas.

In most cases, the valve gets jammed and stuck in one position causing water flow control issues.

Excess air in the chamber:

If there is too much air in the combustion chamber of your boiler, you can expect increased usage of gas. This, again, happens when the boiler is older or there is a lack of proper maintenance.

How much does it cost to run a boiler per month?

On average, the cost could range from about $30 to $60, with the former being the cost incurred when your boiler is working or a 1- or 2-bedroom apartment. With bigger or more rooms in the house, you could expect the bill to go up higher.

The total cost to run a boiler would depend on a few important factors. This includes the area you live in and how much you use the boiler.

Other than that, how you make your fuel payments and the way your house is insulated also play a part in the total bill at the end of the month. It would also vary depending on the type of boiler in use and how big the rooms or house is.

Additionally, the condition of the boiler and whether it is too old or new would have a noticeable difference in the cost of running a boiler per month.

How to calculate boiler gas consumption?

If you wish to do a calculation to find out how much gas your boiler is consuming, this is how you may do it:

Find manufacturer manual:

Before jumping into the calculations, you would first need to identify and determine a few factors required for the calculation.

You would be able to find the value from the manufacturer and manual of the boiler.  

To start, you need to measure the area in which the boiler is heating. For instance, gas utilization is higher when the area covered by the boiler is more.

Find gas calorific value:

For the next step, find out the gas calorific value. This value would be different for the type of fuel or gas that is being used and hence the price would vary accordingly.

Know thermal efficiency:

Following that, you would need to find the thermal efficiency of the boiler, which would also vary based on a few factors like the total heating area.

Know the boiler output size:

Next, you would need the output of the boiler. This number can also vary and has a count of 700,000 kcal when the boiler is on 1 ton.

Use formula:

Last but not the least, you can use the following formula to calculate the gas consumption of your boiler:

The output of boiler/ Calorific value of gas/Thermal efficiency of the boiler.

How do I reduce the gas consumption of my boiler?

If you feel that your boiler is using too much gas, you may want to check whether the gas prices have increased before anything else.

However, it is most likely that your boiler is consuming more gas due to usage and hence you would need to implement ways to reduce it.

Service boiler:

Since the boiler consumes more gas when it becomes old and worn out, the first thing you may want to do is have the boiler checked and services by a professional.

You can reduce gas consumption by at least 10 percent if you service your boiler every couple of years.

Insulate house:

If your home has poor insulation and hence poor efficiency, so will your boiler.

To reduce the gas consumption of your boiler, you would then want to make sure that your house is well insulated, this includes the doors, windows, and the roof as well.

Some people even droughtproof their home walls for better efficiency.

Adjust time and temperature:

Next, you would want to play and adjust the temperature and time settings of the boiler to maximize efficiency and minimize the consumption of gas.

One way to do this is by reducing the stack temperature to take off the pressure. Other than that, you can also regulate the burner to see what works to deliver lower costs of gas consumption.

Get economizer:

Get yourself an economizer for the boiler so that it can save on gas while the boiler is at work.

Since it would make the water flowing into the boiler hot, your boiler would consume less gas for cold water.

Final Thoughts

A boiler would consume more gas if the boiler is old and faulty. Other than that, a broken thermostat, poor maintenance, and bad insulation contribute to more gas consumption. But the consumption would be same as the size. The total monthly bill incurring could be from 30 to 60 dollars on average.