Pressure switch solution...maybe.

Moving the pressure switch out of the well casing seems to be required.  Switches that can withstand the moisture tend to have low amperage capabilities and would need to be connected to a relay to switch the current needed.  That seemed to add more complexity than I wanted although not completely unreasonable.

After looking for a device that could change water pressure to air pressure and finding none I decided to make one.  I selected a SHURFLO accumulator as the foundation.

These are used to smooth out pressures in a water line.  In the above picture, the top is filled with air at about 20 P.S.I.  As water pressure on the bottom increases the bladder move up proving a reservoir of water that is available the instant a faucet is opened.

Since I want to connect the air valve on the top of that tank to my pressure switch the water pressure would no longer have the 20 P.S.I. to push against and the bladder would expand far beyond it's intended tension.

The reason for this device was originally to change water pressure to air pressure.  So I considered filling the top of the tank with a liquid for the water to push against.  My first thought was to use anti-freeze but that stuff is poison and if the bladder ruptured for any reason the poison would be bled into the water supply.  After that thought ran through my mind I wondered if RV Anti-freeze would work.

It turns out that RV anti-freeze actually still freezes...solid.  What it does not do is expand.  That means that if you drain your RV tanks and fill all of the lines with the "pink" stuff they will still freeze but not break.  Well, so much for that idea.

Next I find information on a new "pet-safe" anti-freeze.  Here is how the product is presented:

"At the National Meeting & Exposition of the American Chemical Society on Wednesday, researchers at ACTA Technology proposed a new alternative adapted from a common food additive. In addition to being safe for kids and pets -- as well as cheaper to dispose of because it's nontoxic -- the patented product may even be more efficient than the poisonous standard.

Propylene glycol is already "generally recognized as safe" by the FDA..."

The part where it says "generally safe" caused me to look deeper.  It seems that propylene glycol is used in lots of food items including:

Margarine

Dry cake mixes

Soda pop

Frozen deserts

Kibbles and Bits dog food

Many ranch dressings and barbecue sauces

Frosting for cake and cookies

Flavored coffees

And Fireball Cinnamon Whisky.

It seems that “generally safe” is allowed in the U.S. but not in some European countries.   Although some 4,000 products use this chemical it seems to be a bad idea to have it undiluted into the water stream.

Ok, one of the items on that list got my attention… Fireball Cinnamon Whisky.  It turns out that it will not freeze until below -12 degrees.  I think I have found my anti-freeze liquid… Fireball Cinnamon Whisky.  Since the SHURFLO accumulator holds 21 oz. that would require about 11 oz of whisky.  The worst that could happen if the bladder ruptured is the water would taste like cinnamon.