Winterize fresh water gravity fill tube?

Dayle1 wrote:

skipnchar wrote:
Even when just left alone, as long as it is not constricted anywhere so any ice that forms has plenty of room to expand, no damage would be done to the fill tube. A shot of RV antifreeze is just fine if it makes you feel better but probably not necessary.

X2

While I generally do agree with this, there can sometimes be problems with this method. You see..water freezes from the outside in. So the ends of the settled water section can freeze. Then as the inner portion of the water freezes the ends cannot push out or up the hose. That makes the expansion area (as it freezes) grow in the middle of the water low point. If it "bubbles" out enough, it "could" split the line in that area. This has not happened to me in any RV with PEX tubing. But it has happened to me in garden hoses that have frozen in small low point areas.

skipnchar wrote:
Even when just left alone, as long as it is not constricted anywhere so any ice that forms has plenty of room to expand, no damage would be done to the fill tube. A shot of RV antifreeze is just fine if it makes you feel better but probably not necessary.

X2

Don't forget to blow out the black tank rinse system.

Even when just left alone, as long as it is not constricted anywhere so any ice that forms has plenty of room to expand, no damage would be done to the fill tube. A shot of RV antifreeze is just fine if it makes you feel better but probably not necessary.

I pretty much do all that is mentioned here, the only reason I ran anything into the tank was for the gravity fill line, which I can't get at since its enclosed in underbelly, obviously blowing it out still leaves a small amount in the lowest point of the hose but not enough to do damage i expect.. and also the line coming from tank to the inlet side of pump which I can easily blow back into tank to drain once I detach the pump and suck up the A/F. Oh yes I live in International Falls MN.. this is my 3rd RV.. just the first time I have had to deal with the fill tube having a trap in it..

Can you reach the fill line? Just grab it and lift it up, allowing the water to enter the fresh tank.

As for the rest of the water system. I've used only compressed air to blow out the lines of my trailer. Antifreeze in the sink and shower drains only. It has survived -20*F.

Blowing the line should clear the low point. Open the low point drains and let all the water run out. Blow out the black tank flush system. And blow air thru the city water connection. Then re-cap the low point drains.

But I never put any A/F in any fresh water tank or the water heater. Drain these completely. I blow compressed air into the water heater until no more water comes out. The set the water heater by-pass. Take the shower hose off the shower and connect to the inlet side of the water pump. The other end goes into the jug of A/F. Turn on the pump. Run around opening all the cold/hot water faucets until pink runs out. Also flush the toilet until pink runs out. Make sure you open the outside shower faucets, too. And Clothes washer if you have one.

Let the pump bring the system up to pressure with A/F. When it stops, disconnect the hose at the pump. Poor some A/F into the drain traps. Your done.

Since there is no A/F in the tanks, it is a very simple task to de-winterize. Simply run freshwater thru the system to flush the lines. No residual A/F taste.