I call the house phone daily in AM...if it rings...no problem...busy...big problem and next call is to service company.
I saw the device that will turn on a light
if heat fails. My problem is I never camp close enough to my home to see the light
and my other home was a 6 hour drive away!
My "call method" worked for over 10 years and did save the day once in those 10 years. I called from the U.S. Virgin Islands and got a busy signal...waited 30 minutes and called again...still busy...then called the service folks...problem solved before noon.
This is one of many such devices. It is the most cost effective.
The idea of draining the pipes is a complicated one and requires many plumbing modifications and a compressor to do right...always a very "chancy" proposition.
I owned a seasonal lakefront camp for a dozen years and know all the problems associated with draining the water pipes, well pipes etc...you will need a real professional plumber who services a lot of seasonal homes to get it right the first time!