Free Gas Rate Calculator
Quickly Measure & Gas Rate Appliances
Get an integrated version of this calculator in the full version of our software.
GAS RATE
M3/HR
0.00
GROSS
KW
0.00
NET
KW
0.00
How to use this Gas Rate Calculator
Getting started:
- Select the gas type.
- Select the measurement system.
- Turn off all other gas appliances.
- Allow the appliance to warm up for 10 minutes.
Then, depending on metric or imperial gas rating:
Metric:
- Take an initial meter reading and enter it in the text field.
- Start the timer.
- When the timer finishes, take and enter a final reading in the text field.
- Click anywhere and the results will be calculated.
Imperial:
- Start the timer.
- Stop the timer when the test dial completes one revolution.
- Record the results.
How to use this Gas Rate Calculator
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How gas rates are calculated
Gas rating an appliance is a fairly simple calculation, but there are a few different things that need to be taken into account. Whether you’re gas rating an imperial or metric boiler using natural gas or LPG will all change your resulting figures, for example.
Here is how our calculator works:
The constant values used:
- The calorific value* (CV) for natural gas: In our calculator, we use a value of 10.76 kW/m³ (1040 BTU/ft³)
- The calorific value* (CV) for LPG: In our calculator, we use a value of 26.39 kW/m³ (2516 BTU/ft³)
- The gross to net conversion rate: 1.11
- ft³ to m³ conversion rate: 0.0283
- BTU to kW conversion rate: 3412
*Note that calorific values will vary slightly based on the gas supplier and location.
Metric gas rating calculations:
Gas rate:
3600 (seconds in 1 hour) * (final reading - initial reading)(m³) / test time (s)
e.g.
3600 * 0.053 / 120 = 1.59m3/hr
Gross
Gas rate * CV (kW/m³)
e.g. (using the CV of natural gas):
(3600* 0.053 * 10.76) / 120 = 17.11kW
Net
Gross / net conversion rate
e.g.
((3600* 0.053 * 10.76) / 120) / 1.1 = 15.41kW
Imperial gas rating calculations:
Gas rate:
3600 (seconds in 1 hour) * ft³ to m³ conversion rate / timer (seconds)
e.g.
(3600 * 0.0283) / 45 = 2.26m³/hr
Gross:
3600 (seconds in 1 hour) * CV (BTU/ft) / timer (seconds) * BTU to kW conversion rate
e.g. (using the CV of natural gas)
(3600* 1040) / (45*3412) = 24.38 kW
Net:
Gross / net conversion rate
e.g.
((3600* 1040) / (45*3412))/1.1 = 21.97 kW
Metric gas rating calculations:
Gas rate:
3600 (seconds in 1 hour) * (final reading - initial reading)(m³) / test time (s)
e.g.
3600 * 0.053 / 120 = 1.59m3/hr
Gross
Gas rate * CV (kW/m³)
e.g. (using the CV of natural gas):
(3600* 0.053 * 10.76) / 120 = 17.11kW
Net
Gross / net conversion rate
e.g.
((3600* 0.053 * 10.76) / 120) / 1.1 = 15.41kW
Imperial gas rating calculations:
Gas rate:
3600 (seconds in 1 hour) * ft³ to m³ conversion rate / timer (seconds)
e.g.
(3600 * 0.0283) / 45 = 2.26m³/hr
Gross:
3600 (seconds in 1 hour) * CV (BTU/ft) / timer (seconds) * BTU to kW conversion rate
e.g.
(3600* 1040) / (45*3412) = 24.38 kW
Net:
Gross / net conversion rate
e.g.
((3600* 1040) / (45*3412))/1.1 = 21.97 kW
Why are there different calorific values (CVs)?
Every type of fuel has a calorific value, which is a way of measuring how much potential energy is contained within it. As it is combusted in a boiler, this energy is released.
There will be some natural variation amongst the CV of gas supplies due to differences in the chemical makeup and concentrations of gases.
Here in the UK, gas engineers can use a standard CV for their gas rate calcuations and not worry about minute differences.
A new addition to your toolkit
Our gas rate calculator can help you get an accurate gas rate recording in seconds.
Up-to-date Formula
100% carefree, reliable, and accurate results
No matter how many times you’ve done it, gas rating an appliance is a tedious process easy to make careless mistakes with. By using a gas rate calculator, you’ll be able to get reliable and accurate results you know you can trust – for both natural gas and LPG – without having to manually calculate it each time. There's no need for the process to be complicated, so why do it the hard way?
Tried and Tested by Professionals
Used by thousands every day
We know filling out a gas safe certificate comes with a great deal of responsibility. The last thing you need is to feel like you need to double-check results. Our software and gas rate calculator is regularly used by over 6000+ companies to reliably and accurately gas rate appliances. From this, we’ve continually refined and improved the user experience of our gas rate calculator - both here on the web and in our software.
“I can honestly say this software tool is every bit as important to me as any other tools/devices.”
Since setting up my own business about three years ago I’ve been using Gas Engineer Software and I can honestly say this software tool is every bit as important to me as any other tools/devices required to carry out my daily tasks as a domestic gas engineer specialising in installation, service and repairs. Would definitely recommend this software to anyone that wants a more professional approach to running their business and spending less time doing admin.
Stuart Kershaw, Bolton
TEK Heating Services
Intuitively designed
Gas rate an appliance in minutes
Take readings and calculate gas flow on the fly. If you download our calculator app or sign up for our software, results are saved and you can always come back later on and write down the result when convenient. Our calculator has also been designed to be as intuitive and simple as possible without reducing its core functionality.
Part of the Gas Engineer Software ecosystem
Use on the web or in our software
A gas rate calculator is a cool app - but the team at Gas Engineer Software works on much more. We offer an all-in-one job management platform designed specifically for gas engineers like you, helping save time, money, and effort. Our gas rate calculator is seamlessly integrated with our platform and plays a small role in the bigger picture. So whether you need scheduling tools, digital gas safe certificates, and so much more, we're here to help you find success.
Frequently Asked Questions
What is a gas rate calculator?
Gas engineers frequently need to calculate the gas consumption of an appliance to determine whether it is operating safely and within manufacturer specifications. A gas rate calculator is a simple tool designed to help you quickly and accurately calculate this rate based on a few simple inputs. It helps you save time, reduce human error, and get results you can trust.
How do you calculate a gas rate?
Calculating an appliance’s gas rate using the calculator is made simple with a calculator like ours. The gas rate refers to the volume of gas passing through the appliance within a certain period of time.
If you are calculating in metric, all you need to do is take an initial gas meter reading, start the timer, and then take a final reading. For imperial, you simply have to start the timer, stopping it when the dial completes one full revolution. The calculator does the rest.
Are gas rate calculators reliable?
The short answer is yes. Our calculator is used by thousands of gas engineers each day. We’ve made sure our formula is accurate and up to date. It also helps eliminate the chance of human error.
What is the benefit of using the gas rate calculator with Gas Engineer Software?
A standalone calculator is a great tool to keep in your belt. But its true value is unlocked when used together with our software platform. Once you get a gas rate result, our software will automatically store it, so you won’t have to redo the test if you forget where you wrote it down. Your results are also integrated with our electronic gas safe certificates, making the whole process quicker and easier.
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