[help] stop of program during running

hello,

i have a problem with my sketch.
my sketch is for my central heating system.

is work well but only for a time.

after a time it stop alone .
after a time it go out of loop fonction.

somebody can check my software?
i need really help.

thanks

chaudiere_DHT_eth.ino.ino (17.6 KB)

This

String readString;

is a possible source for that sort of problem. Strings (capital S) don't work well in the small memory of the Arduino. They can eventually corrupt the memory.

Use strings (small s) which are arrays of char terminated with a 0. That is what is used in Serial Input Basics

If that is not the problem may I suggest that you write an explanation of how your program works - there is a lot of code.

...R