DHT controlled stepper motor

Other Hardware Sensors
10

I'm not sure what you're asking, but

if (temp_sens >= temp_threshold) {
  open();
} else  {
  close();
}

looks to me to be sufficient.
It's not really a question of efficiency, more of making the code as simple as it can be, and that way, bugs have fewer dark corners to hide in.

You didn't answer my earlier question about which LCD allows more than eight custom characters.

And about those missing code tags...you can edit them into your earlier post.