Support Center: Guides & FAQs

To maintain a compressed air flow meter, you should follow these steps:

• Regularly check the calibration of the flow meter. It’s recommended to calibrate the meter at least once a year or as often as specified by the manufacturer or regulatory requirements.
• Keep the flow meter clean. Dirt, dust, and debris can accumulate on the flow meter over time, affecting its performance. Clean the meter regularly with a soft brush or compressed air.
• Check the installation of the flow meter. Make sure that the meter is installed correctly and that all connections are tight.
• Check the process conditions. Make sure that the process conditions, such as temperature and pressure, are within the range that the meter is designed to handle.
• Check the flow rate. Make sure that the flow rate through the meter is within the range that the meter is designed to handle.
• Check the control unit and software. Make sure that the control unit and software are working properly, and that the settings are correct.
• Keep the meter lubricated. Some flow meters require lubrication to function properly. Consult the manufacturer’s instructions to ensure that the meter is properly lubricated.
• Replace the sensor and other wearable parts as needed. The sensor and other wearable parts of the flow meter may need to be replaced over time. Consult the manufacturer’s instructions for recommended replacement intervals.
• Keep the flow meter protected. Flow meters are often exposed to harsh environments, so it is important to protect them from extreme temperatures, vibration, and other environmental factors.

It’s important to consult the manufacturer’s instruction manual for specific maintenance procedures and recommendations. It’s also recommended to contact the manufacturer or a qualified service technician if you are unsure about how to maintain your flow meter.

Thermal mass flow meters for compressed air are flexible instruments that can also measure the flow of many other gases. Their working principle is based on heat transfer. A heated sensor loses heat to the passing gas and this cooling effect is proportional to the mass flow. By monitoring the temperature change, the meter determines the actual gas flow.

Because each gas has its own thermal conductivity and molecular properties, modern instruments use software algorithms to adjust these factors. A sensor calibrated in air can therefore be adapted to nitrogen, oxygen, carbon dioxide or other compressed gases by applying the correct gas settings.

This makes thermal mass flow meters a reliable choice for a wide range of gas applications where accurate mass flow measurement is needed.

A water flow meter can be used to measure the heat recovery of a compressed air system by measuring the flow rate of the water used to cool the compressed air. The heat generated by the compression process can be recovered by passing the compressed air through a heat exchanger, where it transfer heat to the water.

By measuring the flow rate of the water before and after it passes through the heat exchanger, the amount of heat transferred from the compressed air to the water can be calculated. This can provide information on the efficiency of the heat recovery system and identify any potential issues.

Due to the fact that pollutants are in the ambient air which is sucked in by the compressor also the compressed air is loaded with dust, particles, humidity or oil vapors. Particles are harmful for many production processes, e. g. electronics industry, pharmaceutical industry or R & D labs and therefore have to be monitored reliably.

The compressed air has to pass many obstacles between the generation of the compressor to the point of use. This leads to a pressure drop.

• A filter element is loading with particles, oil aerosol, or other contamination.
• A blockage or restriction is developing in the purification or piping system.
• Flow demand has increased, which naturally raises differential pressure at the same component.
• Pressure take-off points or impulse lines are partially blocked, creating false readings.
• The differential pressure transmitter requires verification or maintenance.

• Compare the actual value with the normal clean-filter baseline at the same flow condition.
• Inspect and replace filter elements if the pressure drop exceeds the maintenance limit.
• Check for restrictions, valve position changes, or abnormal consumption downstream.
• Inspect the pressure connections and impulse lines for blockage or condensate.
• Verify the transmitter reading with a reference if the trend does not match process behavior.

• The measuring point is upstream of the final filtration stage.
• Filter elements are overloaded, damaged, bypassed, or installed incorrectly.
• The system was recently opened, serviced, or disturbed, releasing residual contamination.
• Separators or drains are not functioning correctly or are releasing carryover particles.

• Sampling tubing, fittings, or quick couplings are contaminated and releasing particles.
• The sampling line has not been purged long enough before measurement.
• The instrument itself is contaminated or requires cleaning.
• The instrument requires verification or calibration.

• Install a zero-particle filter directly upstream of the instrument – this is the most effective way to isolate the source of high readings. If particle counts drop to near zero with the filter in line, the high readings are coming from the system. If counts remain high, the instrument or sampling system is contaminated.
• Inspect the sampling tubing and connections – contamination can accumulate in sample lines, hose interiors, and quick couplings; use clean sampling accessories suitable for particle measurement and replace if needed.
• Confirm the measuring point location – verify the measuring point is after the final treatment stage relevant to the target ISO 8573 class.
• Inspect filters, separators, and drains – check for correct operation, service condition, and proper installation.
• Purge the sampling line adequately – allow sufficient time to flush out particles from the sampling pathway before taking a measurement.
• Compare with historical baseline data – use reference measurements or known clean air to verify instrument performance.

• Activated carbon stages are saturated or bypassed.
• The compressor is carrying over more oil than normal.
• The measurement point is located before the final adsorption stage.
• Hydrocarbon contamination is entering from ambient intake air or connected equipment.
• Separator and filtration performance is degraded upstream.

• The sensor requires zero verification, service, or calibration.
• Inlet tubing, fittings, or connections are contaminated with hydrocarbons.
• The sampling line contains residual oil or vapor from previous measurements.
• The instrument itself requires cleaning or has drifted out of calibration.

• Install a zero-filter or use clean compressed air upstream of the sensor – connect a high-quality activated carbon filter or certified clean air source directly upstream of the instrument. If oil vapor readings drop to near zero, the high readings are coming from the system. If readings remain high, the instrument or sampling system is contaminated.
• Inspect inlet tubing and sampling connections – contamination can accumulate inside sample lines and fittings; check for oil residue and replace tubing with clean sampling-grade hose if needed.
• Verify the measurement point location – confirm that the measuring point is downstream of the full treatment train intended to remove oil vapor.
• Inspect activated carbon filters and adsorption cartridges – replace them if saturated or if service life has been exceeded.
• Check separator and filtration performance – review upstream components for oil carryover or bypass.
• Review compressor operating condition – assess lubricant carryover and overall compressor health.
• Perform sensor zero verification and calibration – especially if the reading increased gradually over time, indicating possible sensor drift or saturation.

A desiccant dryer, also called an adsorption dryer, removes moisture from compressed air using a porous drying material such as silica gel or activated alumina.

Compressed air flows through a bed of desiccant. The material adsorbs water vapor, trapping moisture on its surface while the dry air passes through. This process allows the dryer to achieve very low dew points, typically down to −40 °C or lower.Once the desiccant becomes saturated, it must be regenerated. This is usually done in two ways:
• Heatless (pressure swing) regeneration: a small amount of dry air is used to purge and remove the stored moisture.
• Heat regeneration: the desiccant is heated to release the moisture.

Most desiccant dryers use two drying chambers, allowing one to dry the air while the other regenerates the desiccant. This ensures a continuous supply of dry compressed air.

Desiccant dryers are commonly used in applications where very dry air and high air purity are essential, such as manufacturing, laboratories, and moisture-sensitive processes.

A refrigerated air dryer removes moisture from compressed air by cooling it until water condenses and can be drained off.

It works on the principle of condensation. The compressed air is cooled inside a refrigeration circuit. Once the temperature drops below the dew point, moisture turns into liquid water, which is automatically removed. The dried air is then slightly reheated to prevent downstream condensation.

Refrigerated dryers offer effective moisture removal, reliable performance, low operating costs, and a simple design. They are easy to install and maintain and are suitable for many applications such as manufacturing, automotive, pharmaceuticals, and food and beverage.

Their limitations appear at very low dew points, as they typically reach around plus three degrees Celsius. The refrigeration system also requires energy to operate.

Overall, refrigerated air dryers are a cost effective and versatile solution for drying compressed air in a wide range of industrial environments.

A Pitot tube flow meter is a differential pressure device that measures the velocity of a gas based on Bernoulli’s principle. It uses two pressure points. The stagnation port captures the impact pressure of the flowing gas, while the static port records the static pressure inside the pipe. The difference between these two pressures gives the differential pressure, which increases with higher gas velocity.

To determine the mass flow rate, the measured differential pressure is combined with temperature and system pressure. These parameters define the density of the gas, which is essential for converting velocity into mass flow. With this approach, a Pitot tube flow meter provides a reliable method to measure mass flow in compressed air and gas systems, supporting stable operation and consistent consumption monitoring.

A dew point sensor for compressed air measures the temperature at which moisture begins to condense. Keeping this value low is essential to avoid corrosion, contamination, and equipment damage.

Capacitive dew point sensors are widely used because they are accurate, fast, robust, and cost effective. They work by detecting changes in electrical capacitance as water vapor interacts with the sensor surface. These changes allow the sensor to calculate the dew point of the compressed air.

Capacitive sensors offer several advantages. They provide reliable accuracy, fast response times, and long term stability even in harsh industrial environments. They are also far more affordable than chilled mirror systems and suitable for many industries such as manufacturing, pharmaceuticals, food and beverage, and automotive.

Monitoring dew point is essential to protect equipment, maintain product quality, and ensure efficient operation of compressed air systems.

Overall, capacitive dew point sensors are key tools for maintaining dry and clean compressed air across a wide range of industrial applications.

A thermal mass flow meter measures compressed air and gas using convective heat transfer. It contains a heated sensor and a temperature sensor. As gas flows past, it cools the heated sensor, and the meter calculates mass flow based on how much heat is removed.

Thermal mass flow meters offer direct mass flow measurement, fast response time, wide rangeability, low pressure drop, and no moving parts, making them reliable and low maintenance.

They are sensitive to changes in gas composition, not suitable for wet or contaminated air, and work best with clean, dry gases.

Overall, they provide accurate and stable flow measurement for many industrial compressed air and gas applications.