All those in the northern states: If your not traveling this winter don't forget to winterize your rig. Its getting pretty close to time now. Summers over the kids are in school(yeah) and the nights are cooling off. I actually had to turn my heat back on Friday. The wife thought it was cold when the inside temp hit 53.
Re: winterizing

When the gray and black holding tanks are empty-how much antifreeze should be added to the tanks to winterize?


Senior Member
Re: winterizing

The reason for antifreeze is to keep water from freezing. This is not because there is anything wrong with ice, but because water expands when it freezes, and if it is contained during the freezing process, the container is usually damaged.

If the tanks are really empty, why would you add any antifreeze? Any trace of liquid remaining would have plenty of room to expand, so no damage is likely.

Then there is the fresh water tank and the heater tank. Did you drain them? Generally these don't drain all the way, but again, there should be plenty of room for the water to expand when it freezes, so is not critical, and cleaning the antifreeze out of these tanks is a challange.

The place where antifreeze is critical is in the lines, where any trapped water will expand and can split the lines. The right amount is the amount it takes to fill all the lines (comes out at every tap or other water source).
Re: winterizing

hertig: I read in another forum the icemaker and washer/dryer also need antifreeze. Do you agree with this?
Should a little antifreeze go into the city water connection?

No antifreeze in the black and gray tanks makes sense.

Re: winterizing

Yes, you need to get anti freeze into any area where water was. John is correct in your tanks, where expansion is possible you will be fine. But in small areas like ice makers, city water connection, water pumps and the like, you need anti freeze.


Senior Member
Re: winterizing

yes, you want antifreeze to come out of EVERY place water comes out of, so that all lines are completely filled. Washer/Dryer for sure. In AZ, I don't bother with antifreeze, but I do close off the icemaker line and drain it as this is probably the most freeze sensitive area (small line, right next to the outer wall) and we do occasionally get down to 30 degrees for a few hours. If I was running antifreeze and could not completely drain the line and ensure it stayed drained, then anti-freeze through the ice-maker would seem to be appropriate although the concept makes me a bit nervous, i'm not sure why.