Airstream Trailering & freezing weather

[jbailey01]

I would like to travel in my 34' Excella during the cold months of the year in the mid section of the US. What would be recommended to avoid the unit freezing when I towed it from one site to another? I have thought of RV antifreeze in the on board water system and pumping it through before every move. This eliminates camping without a water hookup however. What have others done when traveling in cold weather?

[HowieE]

If you have had heat on in the trailer prior to moving and the daytime temperatures will be above 25 degrees you should be able to move without draining the system.

For hard freezes below that I would suggest blowing out the system before moving and traveling with a dry system. If you trailer has a bypass valve on the hot water heater I would close it before blow down. The hot water heater will not freeze in one day of travel as it is too large a thermal mass.

The small amounts of water that will remain after a good blow down should not cause a problem with plastic pipe but could be a problem with the older copper pipe systems.

I would not use this system if you are going to travel more than the one daytime between campgrounds as the over night drop after a day on the road will present a problem

[bovk]

I would be interested in some ideas as well. I think the pipes inside the AS would be safe all the way below some temperature as mentioned above, let's assume 25 degF. So the problem should be divided to situations above and below the number.
Can the furnace run while towing the AS? That could help with inside piping. This may be model specific depending where the pipes are. Assuming antifreeze in gray and black water tanks (or really empty) or even better empty with antifreeze it leaves the fresh water tank as the main concern.
Could people share experience if the fresh water tank heating works while towing? I just do not like the idea of antifreeze in fresh water tank.

[Protagonist]

My Interstate comes from Jackson Center complete with tank heaters, controlled by a thermostat that keeps the tanks at or above ~45°F. However, the owner's manual advises not to use the tank heaters without a shore power connection or generator power, because they'll drain the house batteries stony dead in about four hours of use.

One thing to keep in mind is wind chill. Remember all those signs that say "Bridge may ice before road" or words to that effect? Driving creates a highway-speed wind around and under your trailer, and wind chill will affect your tanks just like it affects bridges when cold air blows under them.

You could find that your tanks freeze faster traveling down the road than they would if you were parked. On the other hand, if the tanks are only part-full, sloshing water would help break up any ice that forms so it's a slush rather than a monolithic block that could bust your tanks.

[jcanavera]

While blowing out the lines may be an option, nothing is better than to get the RV antifreeze into the lines. My local dealer said that typical 12 volt pumps are unable to generate enough pressure to really get all the water out of the lines. I'd be afraid of residual water being left in the lines which would flow to a low spot, with the potential of freezing up, especially when you are in transit where the wind from the road is infiltrating the various areas of the trailer.

Jack

[Jammer]

Originally Posted by jbailey01

I would like to travel in my 34' Excella during the cold months of the year in the mid section of the US. What would be recommended to avoid the unit freezing when I towed it from one site to another? I have thought of RV antifreeze in the on board water system and pumping it through before every move. This eliminates camping without a water hookup however. What have others done when traveling in cold weather?

I'm writing from Minnesota, where it gets Cold.

In general, the best thing to do is run the furnace while you're on the road. You will use a lot of propane, probably a gallon every four hours. Ideally you would want to be sure that the charge line is working properly though if your trailer batteries are in good shape you can get by without it for shorter trips (6 hours, say). That should work fine down to at least 20 degrees, maybe a little lower, and if it's colder than that during the day you're not going to want to leave the water on anyway.

As Howie notes, for really short trips, under an hour or two, you don't need to do much of anything except be sure the trailer is fully warm for a few hours before you leave and then warm it up again when you arrive.

It isn't practical to fully winterize the trailer every time you move it from site to site -- it takes time to do it right and you need either compressed air or a good deal of antifreeze, and access to a dump station. Many dump stations close in freezing weather.

On the other hand it's worth having some sort of provisions for emergency winterization if you have a furnace failure or something.

[HowieE]

Originally Posted by Protagonist

One thing to keep in mind is wind chill. Remember all those signs that say "Bridge may ice before road" or words to that effect? Driving creates a highway-speed wind around and under your trailer, and wind chill will affect your tanks just like it affects bridges when cold air blows under them.

Wind chill is a factor that only applies to objects that are moist on the outer surface, ie. the human body and Texas coolers. The only effect wind might have on you tanks is if there are holes in the belly pan that allows additional intrusion of cold air displacing the warmer air that is contained in the pan.

The reason for the signs on a bridge it that they do not rest directly on earth and thus do not have the thermal mass of the earth to reduce the cool down factor. The Egyptians discovered this and could make ice at temperature close to 40 degrees by lifting a pan of water off the ground and exposing it to the clear night sky.

Your trailer has thermal mass and thus will slow any cooling effect from the weather. Like any mass or insulation it will not STOP FREEZING it will only delay it if there is not so form of heat added.

[Phoenix]

See post summarizing our cold weather adventure this past winter:

http://www.airforums.com/forums/f368...ml#post1157482

[Silver Otter]

We had no trouble this January, going from Virginia down to Florida, in spite of one 19-degree overnight with light snow and fierce wind on the Old Man setting things up. We didn't hook up to city water, of course, and I didn't dump the following days until we were above freezing. Everything inside stayed fine. I like the idea of running the furnace at about 45 or so while underway. May try that if things get cold this winter.

[TG Twinkie]

I would be more concerned with the tanks freezing when sitting still. If the liquid in any of the tanks is sloshing around due to travel. They will not freeze as quickly when compared to sitting still.
I have been on numerous trips in temps as low as 19 F. The water lines that run thru unheated spaces are more susceptible to freezing. Along with sewer traps that are below the floor. ie tub or shower are easily frozen.
I have installed small fans to push warm air into the unheated spaces and added insulation in places I thought would help. For example: the water lines that feed the galley sink run parallel to the heat duct on the curb side. I installed insulation around the water lines and heat duct in such a manner that the water line is encapsulated in the same space as the duct. Thus the radiant heat from the duct keeps the water lines warm. Of course the furnace has to be in operation.
In my trailer the FW holding tank is in the front and the bath is in the rear. A water line runs from the pump (next to the FW tank) to the rear of the trailer. It crossed over the intake for the refer vent where cold air is drawn in. This was one of the first places to freeze. I rerouted the water line higher on the wall behind the refer to take advantage of the heat produced by the refer.
Keeping cabinet doors open also helps with the dead space heating.
Even with tank heaters there are areas such as the dump valves that will freeze long before the contents if the tank will freeze. Most dump valves are located in outside (unheated) spaces. With the piping to the valves be 3" or less in diameter, they will freeze long before the tanks freeze.