I don't bother draining or flushing antifreeze first. I do this in the spring as the de-winterization and getting ready for the season.
I put 1/2 cup of bleach in my fresh tank and then add 20-30 gallons of water.
I start with the hot water faucet and run it until I smell bleach, this may take a few minutes as the water heater will need to fill, I then run the other hot faucets and then the cold faucets. don't forget the shower and flush the toilet a few times.
I then go for a short drive to slosh it around in the tanks, this also give the sanitation solution time to sit in the pipes.
Drain the lines or run the water until the tank is empty. Refill the tank with about 30 gallons of water and flush out the bleach solution.
If your MH is similar to mine, I put this procedure on my web site.
WINTERIZING / DEWINTERIZING | 2001 Coachmen Mirada 300QB
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