After 23 years, the main control board on my spa (hot tub) seems to have died. Replacement cost: $800US. I’ve often wondered whether it would be possible to replace it with ESPHome.
Now I’m giving it more thought, and wondering if anyone has done anything like this before.
The key functions of this board are to drive 8 relays which run the pumps, heater, light and ozone generator. There are two temperature sensors and one flow sensor. It also drives the control panels in the spa itself.
I see they sell 8-channel ESP32 relay boards. $20 sure sounds better than $800. I’m not sure whether I’d have enough GPIO pins left for a couple of temperature sensors. I could probably live without the flow sensor. Or feed data from the ESP8266 I already have in there, monitoring temperatures independently of the spa controller.
I’d lose the use of the spa’s built-in control panels, since I don’t really know they communicate. From what I can tell, it’s some serial protocol, since I think it’s just two wires. But I’d gain the ability to run everything through HA. I could even set up the default web server in ESPHome and have some crude control that way. A waterproof display would be a nice future enhancement, but not totally necessary just to get it back up and running.
Update: After some more troubleshooting, I think the source of the problem may have been a failed temperature sensor. These have failed before, and I had a spare. For some reason this time it failed in a far more dramatic way, completely killing the display, rather than showing an appropriate error message.
I installed the spare (not trivial) and so far it seems to be working. It looks like it’s reading about 3 degrees F too low, however. I may pursue the ESPHome solution anyway, since I’ve sort of lost faith in the current system. But at least now I have time to think through, plan and test the replacement.
I have the same problem and wanted to control my jacuzzi online with HA and a esp32 board. I have a calaite feast spa with a dumb motherboard, have you found something for this situation? Regards
I managed to trace my problem to a failed temperature sensor which was somehow confusing the motherboard, so that project is on hold for now. I still want to revisit it one of these days.
My thought was to replace the motherboard with one of those relay boards you can buy on line. Then I’d be able to use ESPHome to replace both the basic functionality like maintaining temperature and activating the pumps, as well as logic for things like running the pumps for a while daily.
The biggest problem is with the spa’s control panel display. It’s pretty primitive, and I’m sure it would be possible to do even better with a new display, but getting one to fit in the exact hole, and be totally waterproof, might be an issue.
