controlsfreak.dev /// FIELD REFERENCE LIVE
Live · AHU-1 supply-air temperature loop RUN

The supervisor reads the supply-air sensor; the controller holds it at setpoint by modulating the cooling valve. Watch the loop chase each setpoint change.

Tools for those in controls, built for the field.

The math you don't want to redo at the panel — signal scaling, BACnet/IP, Modbus, psychrometrics, thermistors — plus explainers that walk a whole system end-to-end. No login, no ads, no tracking; view-source still works, and these pages will still run ten years from now.

Latest · Practice — quizzes & drills →

LIVE AHU-1 · holding setpoint v3.1.0 ·
Role Controls Programmer
Industry BAS / Building Automation
Location Northeast U.S.
REV 2026-05-24
Status Active

Hi, I'm a controls programmer based in the Northeast U.S. This is a side project I'm working on while exploring vibe coding. There's a genuine gap in easy reference websites and educational resources for this trade. This site started as just a way to have some easy reference tools in one place, but has expanded to include much more. Teaching those in the trade has been a passion of mine since I began to grow my own knowledge. With this project I aim to do that with a broader audience. I try to verify the accuracy of everything on this site the best that I can, but if anything is incorrect, please contact me and I will ensure I fix the accuracy issue. If there are any specific tools or topics you want to see covered, I want to hear about it!

The path here was a little roundabout. I started college for electrical engineering, and pretty quickly realized that learning the theory without getting my hands on it didn't sit right — I wanted to be doing the work, not just reading about it. Between electronics, electrical, and mechanical tinkering going back to when I was a kid, controls turned out to be the place where all of that overlapped. I left school to find a controls role, and the field's been the right fit since.

Day-to-day, the work splits between new-construction programming, retro-commissioning on existing systems, and the troubleshooting calls that always seem to pile up alongside. Most of it lands on institutional and education buildings — schools, universities — and light industrial sites. The teaching impulse that ended up shaping this site started kicking in once new hires began showing up on jobs alongside me; walking somebody through their first sequence of operations, or just showing them what a real panel actually looks like behind the door, turned out to be some of the more satisfying parts of the trade.

Bug reports, tool requests, or feedback — get in touch.