Dave,
After years of being a "weekender" I've finally arrived at an acceptable solution which works,is easy and reliable...in our relatively mild winters.
For the well house, I have an automatic timer that is set to come on at midnight and shut off at 6:00 am. It provides power to a small electric heater that keeps the temps well above freezing all the time even when not operating. It does not cost much and does the job. The risk is loosing power while I'm not there. In especially cold weather, I ask a neighbor to check on the set up daily to insure that power is present. I'm looking into one of those remote cameras that will show the temperatures in the well house 24/7 on my home pc in Houston.
For the house, I have installed a drain valve that completely drains the water from the lines with one turn. I also leave electric heat on a low temp during my absense.
