Best Combustion Analyzer

Combustion analyzers are multi-functional instruments whose main objective is to help you calculate boilers, furnaces, and heaters’ efficiency. The benefit of having the best combustion analyzer is that it also measures a range of parameters like stack temperature, gas levels, and flue pressure. 

Although fire is one of the oldest human inventions, it can be drastic when it accidentally occurs in your home due to fuel or gas leakage without your knowledge. This is why having a combustion analyzer comes in handy. But, which type or brand of combustion analyzer is the best option to buy? 

This is a question we plan on answering in this post by reviewing some of the best combustion analyzers you can buy today. We’ll also discuss some of the best buying guide practices later on.

How Do You Use a Combustion Analyzer?

When searching on the market, you need to find the best combustion analyzer and perfectly know how to use one. 

Here’s a step-by-step guide on how to use a combustion analyzer.

  1. Turn on the combustion analyzer with fresh air. Make sure you hold the power button for a few seconds until the analyzer is on.
  2. Take the probe and insert it into the gas stream for about 2 minutes, or you can wait until the testing machine locks the reading. 
  3. Check the reading on the monitor. Suppose you only find a single piece of information. In that case, you can use the navigation buttons to observe any other information, including O2, CO, excess air, pressure, efficiency, sulfur dioxide, draft pressure, and nitrogen.
  4. After you’ve done that, the next step involves taking off the simple line and waiting until the oxygen reaches up to 20 percent and the rest of the readings lower up to 15 ppm. 
  5. After that, you can power down the combustion analyzer.

Pro Tip: Always follow the instructions provided by the manufacturer in the manual since combustion analyzers are produced by different brands and come in different models. Therefore, they tend to differ in operating systems.

How Do You Measure Combustion Efficiency

To properly determine the combustion efficiency, you need to subtract the exhaust gases’ heat content, which is normally expressed as a percentage of the heating value of the fuel, from the total fuel heat potential, or the 100%.

Here is another equation to illustrate this:

CE = [CO2/(CO2 + CO)] X 100

Please note that the above calculation’s critical elements are the dry volume concentration of CO2 in PPM and the dry volume per concentration of CO in PPM. PPM stands for Parts per Million for Volume.

What Should Flue Gas Analyzer Readings Be?

The proper flue gas analyzer readings should have a maximum ratio of 0.004 and a maximum CO reading of 350 PPM. Some manufacturers give specifications of flue gas readings for CO2 and O2. The oxygen reading of less than 20 percent and a carbon monoxide reading of 0.2 percent usually indicate contamination. The right carbon monoxide content of flue gas should be approximately 10 percent.

What Is a Good CO Reading?

A good CO reading should be in the mid-level – around 51 PPM to 100 PPM. The higher level is more than 101 PPM if there isn’t anyone experiencing symptoms. The 101 PPM level is usually dangerous and should be prevented at all costs.

Between 40 PPM and 400 PPM are CO readings that will set off your alarm for danger. However, the response time between these PPM levels is different.

Types of Combustion

There are several types of combustion that you need to know. They include:

  • Complete Combustion – It requires the combination of oxygen and fuel. During the combustion process, the reactant happens to be entirely burned in oxygen and leaves a limited byproduct. For instance, when hydrocarbon burns in oxygen, the reaction will produce carbon dioxide and water.
  • Incomplete Combustion – It occurs when there isn’t enough oxygen for the fuel to react fully. Therefore, the byproducts, carbon dioxide, and water aren’t produced but only leave behind CO and soot.
  • Rapid Combustion – It is brought about when rapid energy requires external heat energy for a reaction to happen. This reaction remains live until all the fuel is completely burned up.
  • Spontaneous Combustion – It got its name since no outside energy is needed to start the reaction. Therefore, it occurs spontaneously through temperature increase because of an internal reaction, followed by thermal runaway and the presence of enough oxygen.
  • Explosive Combustion – Just as the name suggests, this type of combustion occurs at a rapid pace. When heat, light, fuel, or sound energy is ignited by force, explosive combustion may occur.

Features to Consider when Buying a Combustion Analyzer


Is the combustion analyzer you want to buy easy to use? This is a crucial question you need to ask yourself. The best combustion analyzer should be user-friendly and offer an intuitive user interface. If you find that a combustion analyzer is difficult to use or understand, it’s probably not a good idea to buy it.


Safety is an essential factor to consider before buying any combustion analyzer. Therefore, you need to check and ensure that what you’re buying keenly can offer you the best safety and reliability. Buy a combustion analyzer that is worth the money it’s being sold for.


When buying an electronic device, it’s always good to learn whether it’s easy to maintain or requires too much work. Most combustion analyzers are easy to maintain, although some are not. Therefore, it’s important to consider this factor before making any purchase.


How accurate is the combustion analyzer? The last thing you want is an unreliable product because it may end up causing you more damages than preventing any accidents. Therefore, it’s important to check on reviews and keenly analyze the product before buying it to ensure it’s reliable and accurate.

7 Best Combustion Analyzers to Buy Today

1. The Testo 310 Residential Combustion Analyzer Kit


  • Efficient
  • Versatile
  • Durable
  • Easy to operate
  • Good battery life
  • Decent display


  • The thermocouple may encounter issues after long use
  • O2 sensor may also fail

The Testo 310 Residential Combustion Analyzer Kit is an ideal and the best combustion analyzer to consider buying due to its efficiency and versatility. It tops our list since it only has a few cons, but it’s a reliable tool to use. It is well designed to use more complex flue gas analysis, maintenance, furnace efficiency, and safety check confirmations of residential heating systems.

What makes it versatile is the included advanced sensor technology. The carbon monoxide meter provides accurate readings of oxygen, carbon monoxide, ambient CO, draft & pressure, temperature, and combustion efficiency. Durability is another factor that makes the Testo 310 Residential Combustion Analyzer Kit worth buying and using for your home. 

It has a rugged housing with an integrated and kink-resistant hose that helps secure the combustion performance tool from any leaks or impact. When it comes to using this combustion analyzer, you won’t strain a lot because it’s equipped with a backlit display, quick-start, and an integrated condensation tap and magnet.

Simply put, it’s an instrument that delivers an easy and hands-free application. When you buy it, expect to get a complete set including a probe with cone, particulate filters, extra hoses, a protective hard-shell case, and a pressure plug. It offers increased productivity because, in just 30 seconds, it will be ready to test.

2. Testo 300 Residential and Commercial Combustion Analyzer


  • Easy to use
  • Durable
  • Efficient
  • Intuitive
  • Large HD display
  • It comes in a complete set


  • Not durable enough
  • May encounter issues after long use
  • Requires batteries to function

Testo is a reputable brand that produces excellent products for customers. The Testo 300 Residential and Commercial Combustion Analyzer is suitable for use at home or in a commercial setting. It’s an efficient combustion testing tool that reliably measures the carbon monoxide and oxygen level of boilers, furnaces, differential pressure, temperature, and draft. It’s a flue gas meter that features a sensitive CO and O2 sensor that can last up to 6 years.

The sensor also has a measuring range of approximately 4,000 ppm. Using the Testo 300 Residential and Commercial Combustion Analyzer is also easy because all you have to do is start measuring from the standby mode with only one click of a button. There are also included extra-strong magnets at the back of the meter that gives you a hands-free experience during the measuring process.

Another benefit of this best combustion analyzer is that it comes with a large HD display with a smart touch capability and a structured measurement menu. Therefore, the flue gas detector provides you with all the measurements at a glance. What’s more, it comes in a complete set, including a durable O2 and CO sensor, spare combustion probes, retrofittable NO sensor, easyHeat software, filters, and a rugged hardshell case. 

3. Bacharach Fyrite Intech Combustion Analyzer


  • Easy to use
  • High-contrast LCD display
  • Affordable
  • Reliable 
  • Durable performance


  • It doesn’t do draft tests
  • It comes with a used printer

If you’re looking for a user-friendly and affordable combustion analyzer, then the Bacharach Fyrite Intech Combustion Analyzer fits into this description. It’s the best combustion analyzer to consider buying today and offers some of the best features out there. One good thing about this analyzer is that it comes with a high-contrast LCD display that makes it easier for you to see the recordings.

The LCD display also features backlighting and internal data storage of 10 complete records. It’s a low-cost combustion analyzer that offers rugged, reliable, and long-running performance in a light and handheld unit. It’s a plug-n-play combustion analyzer with B-Smart pre-calibrated sensors that enable a simple in-field replacement, which assists in reducing this instrument’s downtime and offer low-cost ownership.

Another thing that this combustion analyzer does is to reduce the service call times by offering accurate, electronic test results instantly through an intuitive push-button operation. The menu also has six selectable fuel types. Through the provided backlighting, you can easily see the results in any environment. It also offers you the option of getting the output via a wireless printer and reporting kit. It’s an all-in-one combustion analyzer designed to give you accurate results.

4. XLA Alert Portable Gas Detector


  • High sensitive
  • It offers accurate measurements
  • Three alarm methods
  • Portable
  • High-quality
  • Guaranteed warranty


  • Not sturdy
  • Consistently shows an O2 level of approximately 19.7 percent, which is low and causes the alarm to sound.
  • Instructions are difficult to understand

The XLA Alert Portable Gas Detector offers users high sensitivity and accurate measurement. It’s easy to use this combustion since it’s a handheld device that you can also carry around wherever you want. It comes with three alarm methods, adjustable audio, visual, and vibration alert when the preset levels are reached. There’s also an alarm digital time and logging. 

The XLA Alert Portable Gas Detector also has a high-density digital LCD screen display and real-time gas concentration value. In terms of the design, it’s compact with a unique clip design, which makes it convenient for carrying it around. There’s also a Chinese and English operation interface included in this combustion analyzer to make it easier to use.

Another advantage of using this combustion analyzer is that it has a higher quality lower error, made of strong ABS and anti-slip grip rubber. It’s also waterproof, dustproof, and explosion-proof, which makes it relatively safe to use. The detection error of the XLA Alert Portable Gas Detector is better than ≤±5% F.S. and a response time of T<30s. It also includes zero and span calibration options. A greater benefit of buying this combustion analyzer is that you’ll get a 100% guaranteed warranty. 

5. Wohler A 450 L Combustion Analyzer Kit


  • Large 5-inch display
  • Free A 450 app
  • Sturdy and handy
  • Modular design
  • Lightweight


  • Requires batteries to run
  • May encounter issues after long use
  • The case is made of plastic

From design to efficiency, the Wohler A 450 L Combustion Analyzer Kit is suitable for residential and commercial use. This combustion analyzer comes from a brand with more than 85 years of experience in measurement, inspection, and cleaning technology. Wohler products’ development takes place in Germany, and the brand has been represented in the United States for 20 years. 

This modern combustion analyzer is sturdy, smart, and offers all measurements and tuning functions. What makes it efficient is its small and lightweight size, and it’s also enclosed in eye-catching housing. The user-friendly touchscreen controls and smart device connectivity also make it convenient to use in all environments. A multi-stage filter technology protects the robust sensors, but you can also replace them if you want. 

Its modular design allows for quick device service, and the built-in lithium-ion battery allows an operating time of a minimum of 6 hours and even a short charging time. The 5-inch large display also delivers accurate measured values at a glance and also allows the values to be shown as graphics for visually supporting the burner adjustment work. The free A 450 App shows all the values on a smartphone to assist the burner where the measuring and tuning location are far apart.

6. IAQ MAX CO2 Monitor and Data Logger


  • Large LCD display
  • Clean and modern desktop design
  • Efficient
  • Fast and accurate
  • Lightweight


  • The CO2 meter may stop working after long use
  • Inaccurate temperature gauge

When we talk of the best combustion analyzer, the IAQ MAX CO2 Monitor and Data Logger also rank in this category due to the accuracy and speed of results that it delivers. The good thing about this analyzer is that it is specially designed to measure and detect. It’s also easy to use and ready for setup once you buy it. If you want to measure carbon dioxide, temperature, barometric pressure, and relative humidity, this instrument is an excellent option to consider using for that job. 

The provided large LCD display makes the analyzer ideal because it shows the date, clock, battery life, and more. It’s a liquid crystal LCD display that showcases a 3-color code indicator which includes green, yellow, and read. It also features real-time data logging capabilities for further analysis. The NDIR CO2 sensor offers fast, accurate, and precise readings. 

7. UEi Test Instruments C155OILKIT Combustion Analyzer


  • Durable
  • Perfect configuration
  • Includes smoke pump test kit
  • Efficient
  • Reliable
  • Lightweight
  • 1 handle


  • Requires batteries to function
  • May encounter issues after long use

The UEi Test Instruments C155OILKIT Combustion Analyzer is full-featured and configured for oil-fired appliances. It provides ambient and flue gas carbon monoxide (CO) measurements and logging. This best combustion analyzer’s unique features include a high-resolution differential manometer, dual input differential thermometer, and heat exchanger integrity test. 

You can expect to find some of the things in the UEi Test Instruments C155OILKIT Combustion Analyzer are smoke pump test kit, true draft probe, infrared thermal printer (KMIRP2), and thermal printer paper roll. It also includes two K-type temperature probes, two static pressure hoses, a gas pressure probe, AACA4 AC adapter, hard carrying case, and particle filter.

The good thing about this combustion analyzer is that it’s designed to reduce the cost of ownership of comprehensive boiler and furnace efficiency analyzers. It’s specifically pre-programmed to work with natural gas, propane, heavy oil, light oil, biofuel, and wood. The user-friendly interface makes this kit easy to use since it doesn’t require complex manuals or on-screen menus. It’s also perfectly designed for real-world applications.


If you’re searching for the best combustion analyzer, note that it won’t be an easy task because many factors go into play. You can start by checking out the combustion analyzers that we’ve reviewed in this post and even doing more research to gain in-depth knowledge on what to buy.

If you have any questions, please post them in the comments section below and send them through email. We’ll be happy to hear your feedback.