Many new users of the award-winning SMART Air Hood® Balancing Instrument (Series SAH) compare their new readings to those of their old, traditional air flow hoods. While the readings on a 3 cone step diffuser, 4 way diffuser and many return registers are very similar; users have noticed that swirl diffusers, slot diffusers and other directional diffusers give a lower reading on the SMART Air Hood® Balancing Instrument when compared to traditional air flow hoods. Continue reading “Why Does the SMART Air Hood® Balancing Instrument Measure a Lower Flow than Traditional Air Flow Hoods?”
The Dwyer SMART Air Hood® Balancing Instrument now has a TABopts Software option to make a great user experience even better.
The software by Ameritech Data Solutions presented with the HVAC air flow hood was unveiled at the 2018 AHR Expo.
How does a revolutionary and multi-award winning HVAC product become even more valuable to customers and the marketplace? Dwyer found a way to provide greater capabilities. Continue reading “TABopts Software for the Award Winning SMART Air Hood® Balancing Instrument”
The objective for this writing is to inform HVAC technicians and contractors about the limitations of testing equipment currently used for testing, adjusting, and balancing HVAC systems. The need for more accurate instruments is immediate as energy programs are moving toward net-zero energy building efficiencies.
In doing so, HVAC technicians and contractors will struggle with tighter specifications as they tune HVAC systems with instruments that fail to provide the required accuracy and versatility. Continue reading “Advances in HVAC Test Equipment: The Importance of Diffuser Calibration for Flow Hood Measurements”
Methods of Air Balancing
Air balancing a distribution system is needed to properly direct the air flow in order to optimize the system’s design. Flow rates are tested, adjusted, and balanced as cubic feet per minute (CFM) or cubic meters per hour (m3/h). There are two traditional methods for balancing airflow at the terminals. The first is sequential balancing, which involves setting the zone and branch dampers in sequence. However, the most common method of air balancing is called proportional balancing.
- Standard air flow hoods do not correct for diffuser type when balancing a system.
- Proportional balancing is extremely difficult when a mixture of diffusers are present, due to the inaccuracy of standard hoods on slot diffusers.
- Below is a sample of diffusers tested on Dwyer’s Precision Air Calibration Station (Figure A) with a standard air flow hood followed by the Dwyer SMART Air Hood™ Balancing Instrument (Series SAH).
Figure A: Precision Air Hood Calibration Station
Continue reading “Balancing a HVAC System with Multiple Diffuser Types”