When do you wrap the drain lines?

The real concern is when the high for the day will barely rise above 32 or less.
Slow drip may still freeze in the sewer hose. Consider dumping late in the day or when you have a warm shower going.

A question. Are your black and grey tanks exposed underneath the trailer or are they up inside/hidden? If they are hidden they are most likely in a heated space (provided you are using your furnace for heat and not just electric heaters). If that is the case you can drain the tanks, disconnect the slinky, and then insulate just the valve portion of the tank that is outside. The most likely part that would freeze would be the valve/slide gate right at the end. And that would take a lot of cold with the heated liquid right against it. Then when the tank gets full go out, remove insulation, and hook up the slinky and drain. Just make sure you drain the slinky after you unhook so nothing freezes in it. If your tanks are exposed ..... hope you have tank heaters installed.

Thanks y'all! I appreciate the help and the clarifications. We definitely aren't down to the negatives here so hopefully we can get it worked out!

As we live where it gets to -40 we know a bit about freezing water. A slow drip will not work. If it gets down at night leave your water run about a 1/8 inch stream of water. Leave your grey tank drain pulled.

At 20 degrees I would insulate lines. I have been listening to the slow drip nonsnse for years. Running water does freeze just takes a little longer. A slow drip isn't running that fast.

In my 5er & TT where more stuff was out in the open I used heat tape when I was plugged in. On hose or any plastic pipe I first wrapped aluminum tape. (available from Walmart) then tape on heat tape using electrical tape. The aluminum tape distributes the heat better on plastic pipe or hose.

On my 5er the low point drains (the valves on the low point drains) are below my trailer and exposed to the elements. At about 20 they freeze and shatter (very poor design). I cut into those lines before they exited the trailer (in the basement area in my trailer) and installed valves. Now the drains (the freezable part) is in the warm part of the trailer. If you are talking about the low point valves or the fresh water tank valves that are out in the cold, I would be concerned after about 20.

Never

Thanks. One shop said to do that and another said just leave the water on a slow drip and don't worry about it. Leaves me confused...

Hi there. Just asked a local here where it will be going down to teens and 20s tonight. Drains to sewer don't have to be wrapped but in hoses and ground water outlet should be.