How it works
The system works like any standard zone control system with one exception. A static pressure sensor continuously monitors the system static pressure, and if the static goes above it’s set point the zone panel will send a signal to the dampers that are in the closed position (those not calling for heating or cooling) to start to open a small amount to keep the static from going above setpoint. The small amount of air that is allowed to bleed into the non-calling zones eliminates air noise and assures proper airflow.

Tests indicate that bleeding a small amount of conditioned air for a short period of time into non-calling zones has little impact on the zone temperature. In most cases the non-calling zones are above or below setpoint and can absorb the additional conditioned air without causing any temperature deviation.

​​The ESP-400 will work with most manufacturer’s zone panels and standard 24VAC 3-wire dampers.

Why spend time and money trying to cram a bypass damper into a small space when you can install an ESP-400 MODULE in just a few minutes.



  • Easy To Install
  • Lowers Labor Cost
  • Lowers Overall System Cost
  • Eliminates Tight Space Issues
  • Increases System Efficiency​
  • Uses Standard 3-Wire Zone Dampers
  • Factory Set (Easy to Adjust)
  • Prevents Coil Freeze-Up
  • Eliminates Air Noise
  • 10 Year Warranty 


The ESP-400 Electronic Static Pressure Module eliminates the need for a bypass damper when used with most standard zone control panels and standard  3-wire zone dampers. With its unique algorithm, the ESP-400 maintains proper system static pressure.