Well, we went out for our monthly escape from life, this time to Cheatam Annex near Williamsburg Va.
We had snow on Saturday although it didn't last too long it was pretty on the trees while it was there. Temperature got down to 18.7 F on Saturday night (lowest I saw anyway). Earlier in the evening when it looked like it go below freezing I went and disconnected from "city" water and filled the onboard tank up about 1/3 (we have the 40 gal potable mod).
No problems with the water freezing up although we think the cold water line to the shower came awful close - when breaking down Sunday, DW couldn't get flow to rinse the Thetford but after using some hot the cold worked again.
Outside was a different matter - Black water Valve was frozen stuck. Took 10-15 minutes of using a hair dryer and cups of hot water to free up the valve. No problem with the grey water valve or the water in the tank freezing.
Since the TM is so easy to winterize I do it every time we break camp in the winter and before I tow it back to the storage location. The drain plugs are not insulated from the cold and a couple of them were frozen. The furthest forward was not a problem (hot water tank drained through it). The drain on the potable tank was a plug of ice that I had to melt with the blow dryer. One of the rear plugs was frozen shut and again the hair dryer was put to use. Even one I got it open very little water came out but it might have been because the forward drain had been draining the whole time. I still ran the hair dryer on them for a while just to be safe.
I was very impressed with the insulation provided by the TM. We maintained the inside at 65 degrees (a 47 degree delta at the coldest point) using 2 ceramic heaters (one in the back bed and one in the front on the floor) with the propane furnace occasionally kicking in if the temp dipped below 65. That is with one of the sky lights cracked and the window in the door cracked to help minimize condensation.
We will be putting pipe wrap on the stub tubes from the 4 drain locations before I put the TM back in stroage.
Bill