Chapter 1
Introduction
1
The
ENERGY
CONSERVATORY
DIAGNOSTIC TOOLS TO MEASURE BUILDING PERFORMANCE
Chapter 1 Introduction
The Energy Conservatory's (TEC) Exhaust Fan Flow Meter is designed to make quick and accurate measurements
of air flow through residential exhaust fans. The effective air flow measurement range for the Exhaust Fan Flow
Meter is 10 to 124 cubic feet per minute (CFM). The device should be used along with a pressure gauge providing
0.1 Pascals (0.0004 in. w.c.) of resolution in the range of 1 to 8 Pascals. When used with TEC's DG-700, DG-3 or
DG-2 digital pressure gauges, the accuracy of the exhaust fan flow measurement is +/- 10%.
During the measurement procedure, the Exhaust Fan Flow Meter is placed directly over the exhaust fan grille and is
pushed up against the wall or ceiling so that the flexible gasket on the end of the Metering Box creates an air tight
seal around the grille. The pressure reading taken from the Exhaust Fan Flow Meter is easily converted to air flow in
CFM using a flow table attached to the side of the Metering Box. The DG-700 or DG-3 digital pressure gauge can
also be set up to display air flow readings directly in CFM. The Exhaust Fan Flow Meter has 3 calibrated openings
to provide an accurate measurement over the full range of the device. A short handle is provided which can be
attached to the Metering Box using Velcro strips. The handle is designed to allow a standard painter’s pole or
broom handle (not included) to be screwed into the open end of the handle to provide access to exhaust fan grilles
mounted high on walls, or on ceilings.
Exhaust Fan Flow Meter with DG-700 Pressure Gauge