I know this topics has been discussed already several times, but I think my case is a bit different and I thought it might be useful to share it, in case someone else fall into the same problem.
I’m running Hassio Core 2025.12.2 on a Raspeberry Pi 3B.
“Still on a 3B?!” Yes, it works fine, after 8 years on 24/365 it still works great, some new SD now and then but nothing else, so why bothering changing HW?
But recently I installed some Power Supply monitoring extension, and I realized that my power supply unit was not ok… and it has been not ok probably for 8 years!
Oh my…
Therefore, I immediately changed the PS with a proper one, so now… no error, everything smooth for my old, thrusted RPI, poor bastard!
But then… since yesterday my HA started to crash and restart in cycle. Restart, 1 min on, then restart again, on and on endlessly.
I tried anything, disabled everything, even started in safe mode, but the damn thing went on with the same routine.
I tried to put back the old PS (you never know, do you?) but … nothing, same thing.
But then…
Then I realized my RPI is in a box standing against the bookshelf and, changing PS, i had turned it on the other side. Therefore? Air grid and small fan against the bookshelf.
Is it possible? Seems impossible?
I turned it on the other side, still some restart, but longer time every time, and then it began to work properly.
I re-enabled hacs and all the bells and whistle and now it works as it used to do. Isn’t it great?
So, for everyone: PAY ATTENTION TO THE COOLING OF YOUR RPI!
The end