Wall Heater Tamer (Controller)

prusaprinters

I live with an older, rip-roaring wall heater. It comes on slowly, but once it gets going, it doesn't know when to stop. I don't mind adjusting it, but I can't do that so well while I'm sleeping, so I wanted to make something that could help.This project mounts a 28BYJ-48 stepper motor onto the wall heater. It connects to the knob of the heater with a meshing gear that was pretty easy to model and fits with a surprisingly rewarding snugness. The magic happens in esphome's pid sensor, which syncs the stepper position with the pid climate controller in a on_value trigger.It's unlikely that many people will have this exact model heater and be able to use the model directly. However, when I started trying to find a way to automate the heater with a motor, I couldn't find any examples.It's pretty cheap to build. I used a spare stepper I already had in a drawer left over from my blinds, a leftover tmc2209, and a Seeed Xiao esp32c3 I had sitting around. Make sure to do the bipolar mod on the 28BYJ-48.I printed in PolyMaker PolyLite ASA.For the esphome sketch, see this heater.yaml. I used a tmc2209 config which makes it easy to set stepper current without having to use the trimpot. I had hoped to be able to use sensorless homing, but I couldn't get it to work reliably with such a small motor. Maybe next winter I'll remodel this to work with a NEMA8, but for now it seems pretty stable even without the homing functions.