Alnor Balometer Flow Hood Air Balancing Test Equipment

Facility personnel, HVAC contractors, industrial hygienists, building engineers, and safety officers all over the world trust and use Alnor brand instruments.

Alnor Instruments Balometer & Air Capture Flow Hood

EBT721 Air Balancer

ABT701, ABT703, ABT711, ABT713

Using the Alnor ABT Series Balometer / Flow Hoods over a grill or diffuser, the user can measure air flow distribution to verify a structure air balance. The fast meter response and trend values make the ABT Series Balometers the perfect instrument for facility engineers.

6200, 6200D, 6200F, 6200E

The Alnor LoFlo Balometer is the perfect tool to measure low volume air flow. It accurately measures return or supply flows from 10cfm to 500cfm (17 to 850 m3/h). This light weight instrument is great for light commercial and residential use.

Anatomy of a flow hood

The basic design of an air flow hood is comprised of an air flow capture device (hood) and a measurement device (manometer). The flow capture device is typically a nylon fabric hood mounted over a collapsible frame that directs air flow over a sensing element inside the measurement device. The hood typically has one larger open end that is typically sized to fit a standard commercial register of 22 x 22 inches (560 mm x 560 mm), with other hood sizes available. Most flow hoods can measure flow in both direction (supply or return) and have the capability to perform time averaging. Most flow hoods also have multiple flow ranges that are usually attained by changing the readout device, or by using a low flow screen.

Balometers have been used in the HVAC industry for many years as a method of measuring air flow directly at a register or supply. Until recently, most measurements at the register were made only in commercial buildings as it’s a part of a testing and balancing procedure for the HVAC system. Residential HVAC systems were rarely tested in the past, but new residential HVAC standards and weatherization programs are beginning to look at this aspect of the residential HVAC system. In residential systems, the register flows are used to determine if rooms are getting the correct airflow, and to determine total air flow and root out possible duct leakage.