Alnor Flow Hood

Ensuring that a large AC system runs efficiently and comfortably for the people indoors is crucial in office buildings, manufacturing plants, and any other building with many occupants throughout the day. Experienced technicians are able to monitor and correct any problems to ensure this proper environment. They do this by a process known as testing, adjusting, and balancing. We call it TAB for short.

The most essential tool for TAB work is a balometer or air flow hood. There are several names for this instrument and you'll see them used interchangeably in the industry and in this article. "Balometer" itself is a term that Alnor coined in the '80s, but it has become standard terminology now and is basically synonymous with air capture hood and other terms for the same instrument. Another thing to keep in mind while we discuss Alnor air flow hoods is that the TSI brand acquired Alnor but kept the name so that you will see TSI Alnor Balometer as well. We just mention these things here so that your head doesn't start spinning when you see all the different terms flying around. It's all about the same instrument, usually the TSI EBT731, which we'll discuss now.

Essentially, an Alnor Capture Hood is used to measure the air velocity and flow volume at various grilles and registers throughout a building envelope to ensure the best balance for the efficient function of a complete HVAC system. That's a bit of a mouthful. However, it's pretty easy to understand. It is, of course, harder to execute and requires a fair amount of training. The instrument itself consists of a large fabric hood that funnels all the air coming from a register into a base unit containing a high-precision anemometer (air flow tester). The building you're working on will have a standard for the flow rates in the system. So, check what's currently going on (that's "test"), make a tweak if it's off (that's "adjust"), and then make sure that the adjustment is in line with the total system (that's "balance"). It's a bit of an art since once adjustment can affect the whole system, and that's where quality training comes in. However, the entire business is not possible without a professional tester like an Alnor Electronic Balometer.

The standard type of Alnor Air Flow Hood that we just discussed is the most popular and versatile instrument in your TAB arsenal, but sometimes there are particular registers or even entire system with very low volumetric flow rates. For these specific situations, you'll need a "low flow" Alnor Balancing Hood. These will be the TSI 6200 series. Each model has a letter after the 6200 part number, which indicates what size hood fabric is included.

This type of TSI capture hood has a reduced size design to get into tighter and hard-to-reach areas that the larger hoods cannot and has a restricted range of measurement. This limited range saves you some money on the unit but also brings increased resolution and accuracy to your flow measurements. It's important to think of this instrument not as a smaller version of the big tester but as a specialized device for the particular use of reading lower flow rates.

If we were to ask what the most important feature in an Alnor Air Flow Capture Hood is, what might you say? We think the best answer is accuracy. Now, of course, the tester needs to be properly and well designed and fine-tuned for the job you're doing. However, with TSI Alnor, those things are all a given. So, what you want to be sure of for this highly sensitive field of work is that your measurements are accurate.

The question is then, how can you be sure the readings you're getting are spot on? The answer here is calibration. Luckily, every single TSI Flow Hood comes standard with a NIST calibration and a certificate proving it. If you're not familiar with this certification, it is the gold standard in calibration and is recognized by the US government as sufficient to prove the accuracy of readings. This certification means that you, your customers, and any governing body involved in the job can rest easy know that the results you get are the actual results. No second-guessing equals better and faster work which equals more money in your pocket.

Every Balometer Alnor makes comes with a whole range of accessory options. Primarily, these options consist of various hood fabric sizes. You are probably aware that the design, and thus size and volumetric flow, of registers and grilles in a building varies greatly. Sometimes this variation is for functional reasons, and sometimes it's purely cosmetic. Either way, you'll need a capture hood that will fit over the register as closely as possible to trap all the air flow with a minimum of wasted space. TSI Alnor is a leader in this TAB field and acutely recognizes this need. So they offer a wide variety of hood fabrics that you can attach to the base meter. These fabrics will store easily in the case for your balometer so you can be ready for whatever a building envelope throws your way on the job site.

Alnor also offers various carrying cases and tools like a velocity matrix. This device makes it fast and straightforward to do a duct traverse by taking multiple measurements at once and sending them via cable to a handheld anemometer. On that note, while not strictly a balometer accessory, TSI offers a wide range of handheld flow testers that can help you to do your TAB work more efficiently, all standard with NIST calibration, of course.

To close, let's briefly look at the ways that you can use these air flow capture hoods. We talked pretty extensively about TAB work, which is the primary field that you're going to use these meters in. However, there are a couple of other situations where you can make use of a quality balometer. One is HVAC commissioning, where you'll actually use the meter in the design and build of the HVAC system. Another is in just general troubleshooting. Of course, it is like bringing a fire hose to a water gun fight, but if you already have the capture hood, there's no reason why you can't make general troubleshooting as accurate and robust as possible. A final application that is not on many people's radar is cleanroom certification. There are stringent air flow standards in these rooms, and nothing short of NIST-certified accuracy will do. TSI Alnor has you covered even for specialized tasks like that.

Overall, when it comes to precision air flow and volume measurement, you can't beat TSI Alnor Balometers.