What solution can I pour down my plumbing drains when I leave my winter home for six months? When I am gone the temperature reaches 120 and stays in the high 80s during the night. When one winterizes a home, one uses a solution of RV antifreeze, but this would evaporate in the summer.

First be sure to close your water main and open a faucet to relieve pressure, leave it open all summer. Shut of your water heater fuel supply. Your traps will likely evaporate in that temp and you can use the same anti-freeze as in an RV. It will not evaporate as fast as water. Some folks even pour in some light cooking oil.