I would like to use my cottage year round. I have a sand point and draw water 25 ft. The water table is at 15 ft. Frost goes down approximately 4 1/2 ft. I have a crawl space under the cottage. The distance from the well to the pump is approx 20ft. I was thinking of installing a heated water line (1 1/4" pipe insulated with wrap insulation under the cottage.) I was going to heat the room of the cottage that contains my pump and tank. I am concerned about the power going off (it happens quite often) and freezing my main water line coming into the cottage. If it freezes and than the power kicks on will it burst the main pipe? How long will it take to freeze if the power goes out? Is there a product on the market that will enable me to self drain the main water line back into the well when I leave.? If the well water level is at 15 ft than it should be no problem priming water back into the cottage when I arrive. This way the heated line will only be used when I am there. Is there such a thing as a drainable check valve that does not have to be taken apart to drain. I have intention of installing shut offs at inside the cottage to prevent water lines under the cottage to fill with water. I will draw water from the hot water tank as I need it in pails. Your help is appreciated.
If it freezes when there is water in the pump it will burst the pump and probably the lines when it freezes.
I modified a check valve for use as a spring-loaded faucet valve and the same will work for you.
I disassembled an ordinary spring-loaded poppet check; then drilled a small hole in the top of the poppet (opposite side of the screw and spring) so I could solder in a small loop of copper wire.
Install a TEE where the suction pipe turns from vertical to horizontal (below the frost line), with the run of the tee pointing up. Install a pipe from the TEE to above the ground.
Run a wire from the check valve to just above the pipe extension. Cover the end of the pipe with a 4" nipple/coupling/cap assembly.
To drain the check valve, remove the nipple/cap and lift the wire. Use something to hold it up. Release it before you try to start the pump.