This is from the Coachman owners manual off their website. There was no mention of a hose to bypass the freshwater tank. I just blow out the water lines, drain the hot water heater and pour antifreeze down the drains. Takes a little over 1/2 gallon.
Winterizing With Antifreeze Only
Purchase 4-6 gallons of RV approved, non-toxic antifreeze.
Drain all tanks (fresh water and sewage tanks).
Turn water heater bypass valve to bypass position.
Drain water heater.
If you have a water filter system installed, remove the filter from the assembly and discard. (You will need to purchase a new one and install it when de-winterizing your RV.)
Fill the tank above minimum water pump operation level with the RV antifreeze. (Use of a long funnel may be helpful.)
Turn the pump switch 'ON' and open the cold water side of all faucet fixtures. Leave the faucets open until the antifreeze (generally pink in color) flows out of the faucets. Repeat for the hot water side.
Flush toilet until antifreeze is visible inside the bowl and pour one gallon of antifreeze down the toilet to winterize the black holding tank.
Pour antifreeze down each shower/tub, lavatory sink and kitchen sink to fill p-traps.
To winterize gray tank(s), pour one gallon down each related sink drain.
2016 Winnebago 2201DS
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