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Flue Gas Analyser Tips — The Best, Cheapest, and More

by | Sep 11, 2025

Plumbing & Heating

A flue gas analyser is a gas engineer’s most important tool. Without one, any commissioning, servicing, or repair work comes to a complete standstill.

But they’re also the most expensive, the most complex, and at times the trickiest tool to use.

In this article, we’ll walk you through essential flue gas analyser tips, including the best options on the market, the cheapest flue gas analysers, and a bunch of tips from our podcast episode with Dan Tempest – owner of S T Plumbing & Heating and Ambassador for Anton.

Keep reading or jump ahead here:

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What are the best flue gas analysers?

The best flue gas analyser is the one suited for the type of work you do. If you’re looking for well-featured and highly regarded analysers, start with these brands:

Flue gas analyser buying guide

Since the best flue gas analyser will depend on the type of work you do, we’ve broken our recommendations down into different use cases.

Prices at time of writing (September 2025), excl. VAT. For guide purposes only.

 

 Domestic

Key requirements: Standard sensors for O₂, CO, and CO/CO₂ ratio calculation. Must be suitable for BS 7967 compliance and CPA1 assessments.

 Commercial & Light Commercial

Key requirements: High-range CO sensor (up to 10,000 ppm) and the option to add a NOx sensor for environmental checks.

 Commercial Catering (COMCAT)

Key requirements: In addition to combustion analysis, the key feature is an infrared sensor for measuring ambient CO₂ to check kitchen ventilation (for CP42 certificates).

 CO/Fume Incident Investigation

Key requirements: High accuracy at low ppm ranges and compliance with BS 7967 procedures for investigating CO incidents.

  • TPI 709R
    • Price: £420 (base price)
  • Anton Sprint Pro with CMDDA1 add-ons (Gas leak detector, personal CO alarm, ambient air probe)
    • Price: Varies
  • Kane: KANE-CMDDA1 Kit
    • Price: £1,159

 Industrial

Key requirements: Robust build, ability to measure a wider range of gases (like SO₂ and NO₂), and suitability for high-temperature and harsh environments.

 

Note that extra features don’t necessarily make a ‘better’ analyser. You can easily save money by getting one with only the features you need. 

For example, those doing purely domestic work might only need an analyser with tightness testing, flue gas analysis, and temperature differential. Granted, those doing commercial work will need a more complex analyser. 

The cheapest flue gas analysers

Some of the cheapest flue gas analysers on the market are models made by TPI. These devices, such as the DC710, lack a few peripheral features and a screen, meaning you’ll have to connect them to your phone to see the readings. This doesn’t make them any less accurate or reliable at measuring combustion gases, though. 

The TPI: DC710 is one of the best value for money flue gas analysers, currently retailing for around £340. 

You may also find models like the Anton Sprint Pro 2 on sale for not much more.

All Bluetooth-enabled analysers work flawlessly with Gas Engineer Software in the same way more expensive options do, so they can be a great way to save some money. 

You’ll also find some analyser models that use paper rolls to print out readings. These analysers might be cheaper, but you’ll spend lots of money topping up these rolls in the long run.

The most popular flue gas analysers

We surveyed our customers, and from 595 responses, here are the most popular brands:

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For specific models, these were the most popular:

  • Kane 458s (and 458)
  • Anton Sprint Pro
  • Testo 300+

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How does a flue gas analyser work?

Flue gas analysers measure the combustion gases that exit a domestic or commercial boiler’s flue.

Flue gases may contain a mixture of carbon dioxide, carbon monoxide, oxygen, water vapour, nitrogen, and other pollutants. It’s important to measure combustion gases accurately with an analyser to ensure the appliance is operating properly and safely.

In old boilers with a visible combustion flame, gas engineers could determine operating health based on the colour and appearance of the flame. However, modern boilers require a flue gas analyser to understand what’s happening on the inside.

Readings outside safe or manufacturer-recommended figures can indicate that the boiler isn’t operating correctly. And, since some dangerous gases like carbon monoxide can’t be seen or smelled, flue gas analysers are paramount.

There are several analyser brands on the market and, while features vary between brands and models, measuring the mixture of gases is a feature shared by them all.

For example, some analysers can measure pressure differentials and boiler efficiency, use Bluetooth to connect to software, offer tightness testing, and more.

How to use a flue gas analyser

To get a reading from a flue gas analyser, insert the probe into the flue ensuring it is properly connected and sealed. 

After this, the analyser will display the different levels of gases inside the flue. 

For analysers with Bluetooth, you can directly import readings and a dated report to the certificate you’re filling out. Learn more about using your analyser with Gas Engineer Software here. 

Kane Gas Analyser Software Integration

Calibrating your flue gas analyser

Any reading done on an analyser that is out of its calibration date is void. In fact, most analysers will shut down and become unusable when they need to be calibrated.

“I’ve seen people changing dates to get around having to get them calibrated. If you’re of a mindset where you’re wanting to manipulate calibration… it’s madness.”

– Dan Tempest, S T Plumbing And Heating

You’ll need to calibrate your flue gas analyser every year, regardless of whether it’s functioning well or not. The best place to check for more information is the manufacturer’s website. 

Calibrating your analyser isn’t something you can do yourself, and will involve sending it off to the manufacturer. 

Useful flue gas analyser tips:

1. Use software with your analyser

Integrate your Gas Engineer Software account with your Anton gas analyser

The readings you get from your analyser are precise readings. Copying them across by hand allows for the possibility of human error, but is also an extra step when filling out a certificate.

By contrast, connecting your analyser with Gas Engineer Software directly imports the readings into the certificate. At the same time, it’ll attach a report with each reading that contains an uneditable date, calibration info, and all the numbers.

Read our help articles to find out how to connect your analyser to Gas Engineer Software.

“Once you do that digital recording, you are legally covered. It’s a legally binding document that you can prove your analyser is in date for its calibration, the readings you’ve taken are correct, and—no matter what—when you’ve that property perfectly sound.”

– Dan Tempest, S T Plumbing And Heating

2. Don’t leave your analyser in your van:

Analysers are precise instruments that need to be regularly calibrated. Unfortunately, this also makes them vulnerable to condensation build-up and temperature changes. The worst place you can leave your analyser overnight is in your van.

Tool theft is an ever-present problem in the trades, and analysers are likely one of your most valuable (and important) pieces of kit. 

3. Take good care of your analyser, it’s more delicate than you think

Analysers might look like robust devices you can knock around, but they’ve been designed that way to keep them as safe as possible. 

To avoid having to send your analyser in for repair or getting inaccurate readings from a faulty meter, it’s best to treat them carefully. 

4. Don’t let your readings spike

“If you see those readings spiking, you need to get your analyser out.”

– Dan Tempest, S T Plumbing And Heating

If you ever notice your analyser readings spiking, take it out of the flue immediately. This can cause damage to the analyser, usually because you’re pushing the analyser to its operating limits.

5. Run the appliance for a couple of minutes before doing an analysis

Before using your flue gas analyser, keep the appliance running for a few minutes. Allowing it to warm up will ensure the most accurate results possible.

6. Plan your calibration dates around your holidays

This one’s simple, but especially useful if you don’t have a spare analyser: send it off to be calibrated when you plan on going on holiday. You can often send it off via your merchants if you’re concerned about it arriving before you get back, simply picking it back up there.

Doing this will mean you always have your analyser when you need it.

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