We are working on an office building with fan-coils units conditioning office spaces on typical floors and several multi-split ceiling cassette units conditioning technical occupied areas (maintenance room, CFTV room and other O&M staff rooms) located on the first underground floor. My questions are:
Can I use a vane anemometer to take measurements in the external air dumper located inside the fan-coil room? Which methodology (sampling, equipment …) can I use to ensure a more precise measurement?
For the underground external air supply, we have a main rectangular duct and several flexible ducts connecting each cassette unit to the main rectangular duct. I need to measure each flexible duct (measurement at each AHU) or can I measure the total air supplied by the main duct and divide it proportionally to the total air flow of each cassette unit? Which equipment is more adequate for this measurement? I really need make holes in the duct or there is another method less invasive?
The Reference Guide states that measurement at each AHU. However, it doesn’t say which methods or equipment should be used to get a reliable measurement value.
Ante Vulin
Sustainability ManagerYR&G
80 thumbs up
January 30, 2013 - 9:24 am
ASHRAE Standard 111-2008 "Measurement, Testing, Adjusting, and Balancing of Building HVAC Systems" is a valuable resource if you are considering doing these tests yourself. An anemometer is an appropriate tool for some kind of tests. The exact configuration of your air-handler/fan-coil room will determine if you can use an anemometer.
The situation you describe with the minisplits can be treated as a multi-zone system in the 62.1 calculations, and the main OA supply flow would be measured and documented to be sufficient for the critical zones.