Will my water holding freeze up

Do you see all those water tanks supplying water to homes in the towns. Those are not insulated and while they freeze around the outside there is so much mass of water that the inner portion remains open. The same will happen with your tanks. Leave the doors to the cabinets having water lines open and you should have little problem using your on board fresh tank. Just disconnect the outside hose and drain it.

Why doesn't some one make a sticky post for all the questions about handling freezing weather and about hooking up 5vers?

The tanks themselves are usually the last to freeze. Its the smaller lines that you need to worry about, like flex lines in the water service bay, or an ice maker feed line in an outside access.
Also, besides the overnight low, the daytime temp is just as important in determining freeze protection needs. I'm frequently in the low 20's & high teens during winter; but the days are sunny mid 60's. So the lows are only present for a few hours just before sunrise. I never drain or winterize, but I do stick a 60 watt trouble light inside my water bay and drain my ice maker lines, and keep some heat in the rig.
If you're actually using the rig and keeping it heated, then your risk is low at those temps, assuming its warming up well above freezing during daytimes. But each rig is different and you need to learn where the most likely freeze points are on yours.

jayhardy wrote:
It's going to drop into the low 20'on Saturday. I'm in a 2014 Montana Mountaineer. Any ideas on how to avoid my water tank freezing. The shore water is turned off at my state Park. Fort Worden

Lowest we had been before this month was 18 and that was just one night. In Denver two weeks ago the temps went like this:
low High
Mon     12 above    65
Tues    10 above    14
Wed     14 below   3 above
Thurs    8 below    9 above
Fri         1 below    33
Sat        7 above    29
Sun       3 below    29

Kept both furnaces running at 65 degrees, did not use any electric heat as I wanted furnaces running. Ran off fresh tank all week, Cherry Creek State Park has a loop with heated water spigots so we were able to refill.

We also put those thin aluminized insulation sheets between the shades and large windows in the slide since they were facing North, and in the small windows beside the bed.

Only problems were condensation and frost around window frames and using four 40 Lb. propane tanks in 10 days. We were perfectly comfortable, in fact warmer than we like at night, and nothing in the water system or dump valves froze.

I don't know what others are going to say but I probably would go ahead and drain the fresh water tank at its low point. Then fill back up if the temps are going to get above freezing the next day.

Everything inside is going to do just fine with heater running. Your trailer does have heated water tanks and they are enclosed with the underbelly cover.

Be interesting what the Montana Trailer guys are going to tell you...

I have done OK in my OFF-ROAD Camper at those temps but always drained the freshwater tank and blow out the water lines with air compressor...

One of my cold country buddies has rigged up a HYDRONIC hot water heater system using the trailer hot water tank to route hot water lines around his tanks when camping off the power grid....

We are always aware to know where to get more fresh water even if it takes bringing it in using a couple of 5-gallon jerry-type cans at a time... I bet you can find some fresh water around the camp ground somewhere. Of course draining you fresh water tank around your camp site may cause a skating rink for you haha...

NOTE: Looks like my slow typing got me behind everyones answer hehe...

Roy Ken

As long as you have 20 30 gallons in the tank your fine. The lines might freeze but the tanks fine

jayhardy wrote:
It's going to drop into the low 20'on Saturday. I'm in a 2014 Montana Mountaineer. Any ideas on how to avoid my water tank freezing. The shore water is turned off at my state Park. Fort Worden

Absolutely no issue. Disconnect and drop your water lines, make sure all your outside compartments are securely closed and run your furnace which puts heat into underbelly. All 5th of this type are good to about 15 degrees, not sure on Mountaineer but many 5th go lower.