Yes, you can absolutely replace your Edwards EST 3-PPS/M-230 with the EST 4-PPS/M. The EST 4-PPS/M is designed as a direct replacement for the 3-PPS/M-230 model. It offers the same primary power supply functionality with added features for enhanced performance and reliability. The 4-PPS/M is compatible with the existing wiring and configuration of your fire alarm system, making the replacement process straightforward. If you have any specific questions or need assistance with the installation, feel free to reach out to us for support.