Winterizing Fresh Water Drain

I leave the drain valve open on my fresh water tank.

Leave the valve open. If you are concerned about insects, or whatever getting into the open valve....cover it with a fine mesh screen!

Easiest method: drain the tank, then pour a gallon of RV antifreeze into the freshwater tank, open taps one at a time until pink flows. In the spring drain the tank, put a few gallons of freshwater in and run each tap until not pink. If OCD, do it three times. Or carry drinking water in jugs.

I drain the tank, disconnect it’s connection to the pump so water in the tube falls into the tank and drains. I use a 2 position valve to connect the pump input to a tube going to a jug of RV antifreeze. After running every tap, I use a clear tube (I always have it on the tank drain to show water level) and funnel to get a Liter of antifreeze into the tap (vulnerable to freezing) and low point in the tank.

I would open the valve just enough to allow a very slight drip.

In my rig I blow the water lines but the FW tank is strictly pull the plug and let it drain. Some years I close the FW tank valve others I don't - never had a problem and I obviously don't consider it a big deal. If an insect gets into the tank it gets drowned/flushed with bleach water in the spring.

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Thanks everyone. I did use compressed air before using anti-freeze. I know its overkill but I'm OCD about this stuff and Anti-Freeze is cheap. I'll put a rag and rubber band over it and leave the valve open.

You should not rely on gravity only to get water out of the lines. The system will have hills and valleys.

Best for a near dry water lines is to blow them out with air. Even at that you could have a small amount. The amount is not enough to cause problems.
Make sure you open each and every one of the water valves including the toilet and out side showers. Don't forget the shower head hose.

If you are worried about critters.... and want to leave it open, zip tie a small patch of window screen over the opening....

I drain ours and close it....never had a problem. There should be plenty of room for the couple of drops of left over water to expand without damaging anything.

Leave the valve open - there's no reason to shut it. I winterize my TT in the driveway, then move it to back yard with a slightly different tilt. I may not have gotten all of the water out in the drive so I just leave the valve open. Most of them are plastic valves so all it takes is a couple of teaspoons of water to freeze in them and break the valve.

The worst that can happen from an open valve is that you forget to close it when you fill the water tank - so you spill a couple gallons of water.........

I leave the valves open to my gray and black tanks also.

Bill