Air Monitor products use multi-point averaging pitot tube technology coupled with ultra-low, high accuracy, differential pressure measurement to measure air flow in any industrial environment, whether clean or dirty.

Pitot Averaging
The unique pitot averaging technology provides true velocity pressure by directly measuring total pressure minus true static pressure, rather than relying on reference pressures from the back or side of the probe. Competing technologies often require correction factors to account for changes in velocity and density, but Air Monitor’s system uses the Fechheimer method for true static pressure and chamfered impact measurement for total pressure. This approach ensures precise velocity pressure readings—even with pitch and yaw angles up to ±30 degrees—without needing extra corrections.

Differential Pressure (DP)
DP technology is chosen for fluid velocity measurement due to its straightforward relationship: fluid velocity is proportional to the square root of the differential pressure. In ducted systems, total pressure consists of velocity and static pressure; velocity pressure is found by subtracting static pressure from total pressure, which is done by directly measuring the differential pressure between the two. Accurate air flow measurement across a wide velocity range requires a variety of DP transducers with different upper range limits (URLs), including ultra-low ranges like 0.05” w.c. Air Monitor provides ultra-low DP sensing with an Auto-zero function for highly accurate, stable measurements and long-term calibration, starting from 0.05” w.c. transmitters.

We carefully evaluate each application. We analyze available straight run, flow turndown needs, accuracy requirements, potential for plugging, density variation, material compatibility, and the velocity pressure range. Based on this analysis, we design a system that meets the customer’s needs.
Check out the Air Monitor Best in Class Value Propositions:
-Air Monitor provides an engineered systems approach.
-Best accuracy in the industry in low flow, large duct applications.
-AMC transmitters can measure lowest DP in the industry.
-As little as zero straight run required.
-Non-uniform flow profile problem solved: flow conditioners plus cross-duct, multiple measurement points = excellent large duct measurement accuracy.
-Dirty applications are no problem with Auto-Purge feature.
-Excellent stability, repeatability, and accuracy with auto-zero feature.
-Full start-up services: duct traverse studies, training.

Air Monitor products measure:
-Clean airflow
-Dirty airflow
-Combustion airflow
-Air and gas pressure measurement

-Refineries
-Foundries
-Aerospace
-Energy / Power
-Electronics Manufacturing
-Food & Beverage
-Pharmaceutical
-Automotive
-Chemical
-Wastewater
-Pulp & Paper
-Environmental

Air Monitor products are specifically designed to optimize a wide range of equipment types, ensuring accurate airflow measurement and control across diverse industrial applications. The following sections highlight the equipment categories where Air Monitor solutions deliver enhanced performance and reliability.

Combustion Airflow Applications
-Power boilers
-Combination and biomass boilers
-Recovery boilers
-Circulating fluidized bed boilers (CFBs)
-Fired heaters
-Kilns, including lime, ceramic, and cement kilns
-Digester gas systems
-Thermal oxidizers

Dirty Airflow Applications
-Pneumatic conveyors
-Primary air systems for pulverized coal
-Paper drying equipment
-Cyclic nucleotide-gated channels (CNGCs), high volume low concentration (HVLC), and non-condensable gas systems
-Dust collection systems
-Stack flow measurement
-Cement processing equipment
-Quench exhaust systems
-Combustion airflow systems
-Paint spray booths

Clean Process Airflow Applications
-Clean room pressurization systems
-Quench airflow equipment
-Semiconductor manufacturing
-LCD glass production
-Engine test stands and dynamometers
-Product testing environments
-Process development and pilot plants
-Aeration systems for digesters
-Paint spray booths
-Fluidized bed systems

System accuracy depends on the products used, the number, and placement of sensing elements, ranging from ±0.5% to ±2% reading. Air Monitor delivers superior as-installed accuracy and has lenient installation requirements, excelling in low flow, large duct applications, and challenging setups like short straight runs and very large ducts where competitors struggle. When straight run limitations impact accuracy, Air Monitor conducts field tests using three-dimensional traverse methods to measure true velocity vectors, accounting for pitch and yaw angles. These tests follow AMCA, ASHRAE, and 40CFR60 & 75 standards, ensuring the most reliable field verification in the industry.

Air Monitor’s primary elements require no calibration. Their transmitters feature an automatic zeroing circuit that electronically re-zeros at set intervals, eliminating output drift from thermal, electronic, or mechanical effects. In temperature-controlled environments, this function makes the transmitter virtually self-calibrating, maintaining zero within ±0.1% of span (e.g., ±0.00002 IN w.c. for a ±0.02 IN w.c. span). Manual calibration is possible via an electronic switch for the zeroing valve. AUTO-zero transmitters remain stable for years, with customers in critical applications typically calibrating every one or two years.

Air Monitor’s AUTO-purge III protects measurement accuracy in applications with continuous airborne particulate exposure by actively clearing the sensing elements. Here’s how it works. At the assigned time, either the Air Monitor flow transmitter or a distributed control system initiates the purge cycle. The system operates a combination of valves to send high-pressure, high-volume air into the sensing ports for a short time. At the same time, the transmitter isolates itself from over-pressurization. Meanwhile, the output at the last measured value is maintained throughout the purge cycle. Periodic purging maintains the sensing ports of the total and static pressure manifolds in a clear unobstructed condition.

Air Monitor manufactures products for industrial and power systems. Standard industrial products are constructed using stainless steel, ensuring reliable operation in both clean and harsh, particulate-laden environments. Stainless steel withstands temperatures from -20°F to 900°F. The company constructs industrial products using the material needed to match the systems where they are installed. Common configurations include an all welded 3/16” thick casing with all welded flow conditioners and sensing elements. The typical lifespan of an Air Monitor system is 20 to 30 years.
Configurations are available in exotic alloys to handle corrosion and high temperature. Optional tungsten carbide coatings are also available for erosive applications.

Air Monitor has a full line of products designed with materials suitable for industrial applications.
Contact our application engineers to get help choosing the right products for your application and process conditions.

Air Monitor standard products can measure flow in almost any pipe or duct size. Common pipe sizes range from 0.75” to 132” diameter and ducts ranging from 8”x8” to 120”x120”. Moreover, sizes larger than these can be custom designed.

Yes. Air Monitor transmitters provide digital outputs, analog outputs, and network communication options.

Lead times are dependent on the product and the complexity of the design needed to meet an application requirements. Air Monitor custom-builds every product for a specific application, only beginning production after receiving an order. The team constructs and calibrates each unit to meet the application’s unique requirements and flow conditions.