Constant Airflow Regulator 3″


Constant Airflow Regulator for Standard Pressure (0.2” w.c.-1.0” w.c.) applications.

Filed Adjustable Air Flow Range: 10-30 CFM


*** eFlow USA proudly offers the smallest (3”) Constant Airflow regulator on the market. Available with special casing for easy access-only from eFlow USA




eFlow-CAR is a factory set Constant Airflow Regulator designed to save significant amounts of energy and money by precisely controlling airflow into or out of space, regardless of static pressure, and all along providing high Indoor Air Quality (IAQ). eFlow CAR is composed of fire resistant ABS plastic. It contains a self regulating aero-wing and spring piston design to maintain a factory preset air flow. These CARs are designed to operate in pressure range Low Pressure (.08”-4″w.c.), Standard Pressure (0.2″-1″ w.c) and High Pressure (0.6”-2.4″ w.c). They automatically adjust for variable duct pressures caused by building pressure, thermal stack effect, dust build up and other variable factors. This Constant Airflow Regulator creates a cost effective answer to balancing air systems for HVAC and ventilation in high rise buildings, without the requirement for on-site balancing, electrical/pneumatic controls or sensors. eFlow-CAR may contribute to meeting USGBC LEED Building and Passive House Certification. Flow CAR requires no maintenance under normal conditions.

Standard Construction eFlow-CAR: Classified UL R38307 / UL-2043 for heat release rate and smoke optical density.

● UL Classified
● Standard for Energy Efficient Compliance
● Energy Cost Efficient
● Adjustable
● No Specialty Tools
● No Electricity Required
● No Sensors
● Bi-Directional
● Reliable
● Precise
● Easy Installation
● Mitigates Stack Effect
● Factory Calibrated
● Soft Pliable Edge Seal
● CFM setpoint is adjusted through grill
● Promotes labor savings because of easy accessibility

● Energy Efficiency Programs
● Subsidized Housing Projects
● Government Facilities
● Military facilities
● Submarines, Cruise Lines/Marine
● Healthcare
● High Rises
● Commercial Buildings
● Residential Buildings
● Multi-Family Condos/Apartments
● Assisted Living Facilities
● Hospitality/Hotels
● Dormitories and Schools Buildings
● Office buildings
● Bathroom exhaust
● Controlling airflow to obstructed crawlspaces
● Balancing airflow supply from roof-top A/C units
● Balancing supply and exhaust of heat recovery ventilation systems
● Regulating outdoor air-supply into individual room fan coil units or heat pumps
● Balancing airflow on series-fan-powered terminal unit system

Additional information

Weight .119 lbs
Dimensions 3 × 3 × 3 in

High Pressure (0.6 w.c.-2.4 w.c.), Low Pressure (0.08 w.c.-0.4 w.c), Standart Pressure (0.2 w.c.-1 w.c. )

CFM Range

10-30 CFM


Warranty is guaranteed for six (6) years, from the date of shipment, against all defects in material, given that the material has been installed and used under normal conditions. The warranty is limited to the repair or replacement of the material upon its return freight paid to our factory. This warranty is not transferable and is limited to the original end user.

Technical Data Download

Constant Airflow Regulator Submittal Data Sheet

Constant Airflow Regulator Installation And Maintenance Instructions

Constant Airflow Regulator Design Data

eFlow-CAR and Aldes-CAR Comparison Chart