Ask the Expert – Issues with Referencing Outside Air Pressure

Question: I am trying to measure building pressure relative to outside air pressure. However, in doing so, I am seeing fluctuations in the differential pressure readings. Is there any way to minimize or eliminate these fluctuations?

Answer: Whenever you are using outside air for a static pressure reference, fluctuations in outside conditions, especially from wind, can cause erratic differential pressure readings.

By using one of our outdoor static reference probes, such as the A-306 (red) or A-306-A (gray), you can diminish the influence of outdoor weather on your reading. In fact, these outdoor static pressure sensors are specifically designed to greatly reduce impacts from wind and other environmental fluctuations.

Furthermore, depending on the application, you could pair the A-306 or A-306-A with the Series MS2 Magnesense® Differential Pressure Transmitter. The MS2 has digital dampening built in which can be used to further help stabilize the optional LCD display and analog output if needed. Together, these instruments should essentially eliminate any unwanted fluctuations caused by ambient conditions.

To compliment the Dwyer Instruments, Inc. outside air static pressure sensors, we offer a complete portfolio of static pressure sensors for all applications, including sensing in ducts and space (rooms). Dwyer has several different styles based on installation requirements, aerodynamics, and desired aesthetics.  The full line of static pressure sensors offered by Dwyer can be found on our website.