Advice on when to completely shut off water

[iyiyi]

It has been super cold here this year. I have a well. Is there a general rule of thumb when you should completely turn off the water when traveling/leaving the house for extended periods (over a week)?
I have a few water lines that are in exterior walls and I'm nervous they may freeze without being used daily like when I am home.
Between the well pump and propane tankless water heater I'm not comfortable leaving things to drip for that long.

Are there any issues with just shutting off the water and running the lines dry before leaving? Even if something does freeze, I'd prefer it happened once I got home and not while I'm gone with unlimited water possible flooding the house.

Thanks for the advice!

 

[Twowaxhack]

Shut everything down and completely drain everything including water heater and you’re golden. For toilets and traps use RV antifreeze.

 

[pasadena_commut]

This isn't relevant to the freezing issue, but...

We turn off the water inside the house when we will be away for one night or more. The outside irrigation, which is on timers, remains active. We started doing that after when we were just about to leave for a trip I went into the kitchen and turned on the faucet, I think to wash my hands, and the hose under the sink exploded. We also turn off the water heater. This isn't much work for some peace of mind, and because we don't travel much, it only needs to be done a few times a year.