Determining air conditioning usage in a way that is fair to consumers

With the P26 air consumption meter from halstrup-walcher

For rental spaces in buildings such as shopping centres and office complexes, air conditioning costs are typically billed by square meters (resp. square feet), a practice that is often the subject of debate. This is where the new P26 air meter from halstrup-walcher comes into play: the P26 works within the supply air for each rental space, where it adds up the actual amount of air consumed (in cubic meters or feet), making it as easy to track air conditioning costs as it is to track water or electricity costs.

The advantage for the building investor is that air conditioning can now be integrated into the building's energy management. This is a welcome innovation for building owners who rent out commercial space, as it helps improve their property’s sustainability and allows them to target specific areas for savings.

Regular calibration is a must for any pressure gauges used in HVAC applications, in clean rooms, in medical technology and mechanical engineering applications, or as service units. One way of doing this is to send these instruments to halstrup-walcher’s accredited DAkkS laboratory.

In order to avoid having to disassemble pressure gauges and send them to a calibration lab, however, more and more operators are having them calibrated on site. Mobile KAL series calibrators from halstrup-walcher support these efforts.

The advantages of KAL:

• A powerful battery and robust housing provide mobility
• Generates and measures highly precise pressure values
• Pressure sequences can be programmed in advance
• Operation can also be automated via a PC

Interested in learning more about the on-site calibration process?
Then just press the start button:

halstrup-walcher maintains the overpressure – to prevent contamination


Cleanrooms must be kept at a constantly higher pressure than their neighbouring areas in order to prevent infiltration of contaminated air from outside. This is not just required by the relevant standard ISO 14644-4. Every expert in this area knows hour air quality can quickly deteriorate if the overpressure falls by just a few Pascal even temporarily. In the area of semiconductors, dust particles and other pollutants threaten to compromise highly clean finished products. In the pharmaceutical sector, hazardous substances can penetrate highly critical medicines. Obviously, this must be prevented safely.

halstrup-walcher offers high precision pressure sensors, developed and manufactured on its own premises.

One of the company‘s specialist areas lies in the smallest measurement ranges such as those required in clean rooms. These sensors are integrated into three products, which cover every application: The P26 differential pressure transducer for mounting in control cabinets or wall mounting (from which pressure hoses lead to the clean rooms), as the PUC 28 panel version for direct installation in a clean room wall (where it is also possible to view readings for °C and %rF) and the high precision KAL 200 calibration device. This mobile calibration device powered by a rechargeable battery can be used to calibrate all pressure measurement locations regularly on-site and adjust them if required. A pressure generator inside the device generates the target pressure on-site and the internal sensor measures the pressure precisely for the calibration procedure. To ensure that contamination risks never occur in the future.

From on-site calibration to on-board compensation of pressure and temperature

The importance of volume flow measurements to air quality and operating costs has been underestimated for many years. Yet there is now a growing recognition that excessive volume flow in air conditioning and process air systems sends operating costs spiraling upwards. Not only do ventilator fans consume extra energy in moving the surplus air around the system but expensive air conditioning processes (cooling, heating, humidifying or dehumidifying) generate further costs by treating unnecessarily large volumes of air.

Operators and planners have recognized that too little volume flow also creates problems as it results in an inadequate air supply. Moreover, an insufficient volume flow can also lead to hygiene problems – from oxygen deficiency for humans to accelerating bacterial growth in moist, slow-moving air during production processes.

Control cabinet installation of the P 34 pressure transmitter, optimised for volume flowzoom
The measurement technology specialist halstrup-walcher identified this problem and responded immediately by offering a complete package solution:

The company supplies pressure transmitters, which are perfectly tailored to the requirements of volume flow measurement, such as the newly launched P 34 differential pressure transmitter.
Selection, delivery and (on request) installation of the appropriate primary element. The key is to find the correct compromise between the available budget and the accuracy required.
On-site volume flow calibration: we always offer and include on-site calibration for every volume flow measurement point (in accordance with DIN EN 12599). This takes into account and, for the most part, compensates for the individual deficiencies of the measurement location. Based on this calibration, the pressure transmitter is then adjusted to achieve optimum precision.
Volume flow calibration in an accredited laboratory (accreditation under way): In the future it will be possible to calibrate beside primary elements also balometers, ventilators and complete test sections.
Clearly, the difference lies primarily in being able to observe all the relevant aspects of the volume flow measurement as a whole. In practical applications, the accurate, stationary (permanent) measurement of volume flow is essential for maintaining air quality and keeping operating costs under control.