Combustion analysis is important for heating, ventilation, and air conditioning (HVAC) technicians, boiler technicians, and homeowners. It helps ensure that combustion is taking place properly and that gas emissions are within legal limits.
But it is easy for analyzers to get neglected when you’re busy with work. That’s why it’s important to perform proper maintenance on your analyzer.
A combustion analyzer is a tool used to help diagnose the condition of a gas furnace, water heater, or boiler. The tool helps technicians adjust the amount of fuel and air to be used by detecting low and high combustion readings. Performing a calibration on a combustion analyzer helps ensure the accuracy of the readings. This ensures that the combustion process is complete and that byproducts like CO, CO2, and NOx are minimized.
The calibration procedure should be documented on a document called a calibration certificate that includes the date, materials, environmental conditions, and the uncertainty of the measurements. This documentation is needed for traceability purposes and to allow the results of calibration to be accepted by another technician or a lab. Companies that perform calibrations on instruments have to be accredited to do so by one of the international accreditation providers, such as NVLAP, A2LA, or LAB. Having a calibration certificate from an ISO-accredited company allows technicians to be confident that the calibration is valid and accurate.
During the calibration procedure, the technician should make sure that the device they are calibrating is not influenced by other factors such as temperature, humidity, or vibration. They also need to be aware of the differences between the actual combustion process on the equipment and the simulated one on the analyzer. This is to prevent erroneous results, which could be a safety hazard for the technician and the customer.
The technician should also check the probe, tubing, and filter assembly to make sure they are connected correctly and there are no vacuum leaks. After the calibration procedure is complete, they should take a fresh air reading to see that all of the oxygen, CO2, and NOx read 0%. If there are any readings outside of this range, then the combustion analyzer is not functioning properly.
Today’s combustion analyzers tend to be much more user-friendly and easier to maintain than older models. They are designed to be modular, with long-life chemical cells, and to have more advanced features such as data logging. These functions can be used to better communicate with customers and help with the repair and service process.
The most important reading on a combustion analyzer is the oxygen (O2) level. This indicates the degree to which combustion is taking place. It’s important to monitor this reading closely, especially when adjusting the fire for combustion efficiency and stack heat loss purposes. The O2 reading also indicates how much excess air is present in the flue gas stream. Excess air can cause CO and toxins to be released into the house if not properly ventilated or operated. It can also cause soot accumulation on the heat exchanger, which can hold moisture and promote pitting deterioration of the metal.
The O2 sensor is usually in the form of a small glass tube with an electronic chip inside. The chip measures the O2 concentration as it enters the combustion chamber and converts it to a digital readout on the analyzer. The O2 and carbon monoxide sensors need to be kept clean to ensure the highest accuracy of these measurements. After each testing, the sensors should be rinsed with fresh air and stored with the tubes plugged in to prevent contamination, residual odors, or toxic gases from poisoning the sensors.
Carbon Monoxide is a poisonous gas that can accumulate in fuel-burning appliances. It is a result of incomplete combustion, which occurs when carbon atoms do not bind with oxygen atoms to form carbon dioxide (CO2). This is one of the major reasons it is vital to perform regular combustion analysis. Carbon Monoxide can lead to a variety of medical conditions, including headaches, dizziness, confusion, weakness, and nausea. The CDC estimates that unintentional CO exposure causes 500 deaths per year in the United States.
Oxygen and carbon monoxide emissions are heavily regulated by federal, state, and local environmental agencies. Combustion analysis helps assure that these pollutants are not released into the environment violating the law.
A combustion analysis is a digital flue gas testing device that allows professional service technicians to check the combustion products to ensure that they fall within safe limits. This eliminates the need to use cumbersome traditional equipment such as “wet kits,” draft gauges, and smoke pumps.
3. Filter Replacement
A combustion analyzer is a digital device used to test furnace & boiler combustion products. Its reading indicates the amount of oxygen and carbon monoxide in the flue gas stream. This information is critical when determining the condition of your heating system. Professional service technicians insert the combustion analyzer into your heating system’s flue pipe to obtain a reading and ensure it is within the approved limits. This testing equipment replaces traditional combustion testing tools such as “wet kits,” draft gauges, smoke pumps, CO2 gas testers, slide rules & thermometers.
The analyzer includes a probe, tubing & filter assembly that draws the flue gas through a water trap & then into the gas analysis chamber. This is accomplished by a micro-pump that creates suction and conditions the sample so it can be measured accurately by the sensors in the chamber. A carbon dioxide sensor is also often incorporated into the analyzer to check for excess air in non-condensing furnaces. This helps prevent heat loss and energy inefficiency caused by oversized air and incomplete combustion of the fuel.
Sensors in the gas analyzer need to be periodically recalibrated & replaced. The temperature sensor may only need to be calibrated once or twice per year, but the CO & O2 sensors will require recalibration based on how long they have been in use and need to be kept in a clean environment to remain accurate.
The water trap in the analyzer should be emptied and checked regularly for contamination. The tubes & filters should be cleaned regularly as well to ensure that the analyzer continues to function correctly.
These simple tasks will keep your combustion analyzer in working condition and help it provide accurate test results. It is recommended that combustion analysis be performed regularly or anytime any change is made to your propane, natural gas, or oil furnace that could affect the combustion process. This will ensure peak efficiency & safety for your home. Whether you’re an HVAC professional or a homeowner, the right gas analysis tool will help you maintain your system, reduce costly repairs, and improve your comfort.
4. Parts Replacement
A combustion analyzer is an electronic device used by professional service technicians to test heating equipment for proper combustion & safe levels of carbon monoxide (CO). It is typically inserted into the flue pipe of the heating system & reads the digital reading on the screen to indicate whether or not the products of combustion are within acceptable limits. Compared to traditional methods of testing, such as “wet kits,” draft gauges, smoke pumps, CO2 gas testers & slide rules, the combustion analyzer offers a more accurate & efficient way of testing a heating system.
The basic components of a combustion analyzer include an oxygen, carbon monoxide & temperature sensor, and a probe assembly that is connected to the sensor. Each component has a specific function: the oxygen sensor measures the oxygen content of the flue gases, the carbon monoxide sensor measures the CO content of the combustion, and the temperature sensor measures the flue gas temperatures. Some units also have additional sensors that measure pressure, which can be useful for diagnosing a wide variety of issues related to heat exchangers & other building-performance tests.
A common problem encountered in many heating systems is a plugged or cracked heat exchanger. Using a combustion analyzer, technicians can verify that the heat exchanger is not cracked and identify any other problems causing incomplete combustion resulting in unsafe CO levels.
Most modern digital combustion analyzers have the means to remove excess moisture in the gas sample that can damage the pump and sensors. This condensate removal system is commonly called a water trap and should be emptied regularly to avoid the accumulation of excessive amounts of moisture which may affect the accuracy of the readings.
Like any tool, a combustion analyzer can be damaged or fail due to normal wear and tear or improper maintenance. Unlike a simple handheld gas detector, a combustion analyzer is more complex and requires regular care & maintenance to ensure its proper operation. If a combustion
analyzer isn’t properly maintained, the results could be inaccurate, which can lead to dangerously high CO levels in a home or other safety issues. To protect against this, service technicians should always keep a spare parts kit with them on the job to replace worn or damaged components.