LCD goes blank after several hours - backlight still on

Hi all, I would really appreciate some help with this issue I've been having. The LCD appears to be working when I reset the arduino but then after some variable amount of time (~several hours), it goes blank, while the backlight remains on.

Why is this happening? What can I do to fix this?

Attached is my wiring schematic and code.

Thank you in advance.

beer_flow_measure_10_23_2020.ino (5.72 KB)

I also pasted it below for convenience.

Convenience? It is breaking forum rules. Please read the guide in the sticky post, then modify your post above and put in the code tags.

Even better: delete the code you pasted in, go back to the IDE, click Tools->Auto Format, copy that and paste into your post between code tags.

I of course, would be inclined to paste my "boilerplate" advice in this regard, but I do often just get sick of doing so, so I looked at this post and said "Nah!"

So I just checked it to see if Capital "S" "Strings" were being used - they do not appear to be - wondered whether the use of interrupts was appropriate and couldn't find the enthusiasm to complain! :roll_eyes:

Yes, I checked for Strings also. Interrputs certainly not needed here, but should do no harm. Spotted while loops that should be if statements, lcd being updated too often (to show the the time) even though other updates are sensibly limited to once per second, and over-complex floating point calculations of values that are not really needed, and a few more minor beginner mistakes. But nothing, so far, that could explain the display going blank after several hours. Some overheating issue? But what could be overheating, and why?