Holding tanks freezing?

[lornaschinske]

We lived full-time in our Class C in the Tri-Cities area of TN (Johnson City/Kingsport/Bristol) thru the winter of 2007/2008. We placed an old water bed heater pad we had under our exposed fresh tank, then wrapped that in the housetype insulation sheathing (pink stuff or blue stuff... depending on brand) and set the thermostat on as low as it would go. For our water hose hose, we laid one of our heavy duty 100 ft extension cords alongside out 100 ft water hose (yes that was way too long but that was as close as we could get to the house that we were working on), wrapped the cord and water hose in foam pipe insulation (get at least one size larger than your hose diameter) and duct taped the pipe insulation closed. I used pipe heat tape on our water filters (they sit in a 5 gallon bucket lined with Reflectix) and on the 4 ft drinking water hose (also wrapped with pipe insulation) that goes from the filter bucket to the city inlet valve on the Class C. The City inlet and the hose bibb on the house had a foam hose bibb cover on them. We ran electric heaters in the RV so the extension cord stayed pretty warm all winter. Yes it did freeze and snow... often. The pipe tape says to not use on water hoses but we haven't had a problem with it. We also spent the winter in the SW NC mountains in 2008/2009.

For the bus... we will insulate the fresh & holding tanks. Not for freezing weather (which we plan on never seeing again) but for the heat. Our fresh tank on the Class C has a just a thin layer of insulation on it. The water gets so hot while traveling, that I do not need to run the water heater... and I really like HOT showers! The waste tanks... cook (yuk). I still have the pipe tape we used (it will get re used on the bus... just in case). But I don't think we will need to heat our fresh tank. I do want to go to the Grand Canyon and the best time is supposed to be fall and spring but it snows/freezes then at times. That is the only reason we will set up for short term freezes... just for high altitude or late fall/early spring trips.

As for tank size, we are ending up with three 36 gallon tanks (fresh/grey/black). We have found that we don't have room for everything under the bus and have HUGE tanks as well. But we tend to stay in campgrounds and really only need to be without hookup while traveling. We will only wallydock a few nights before pulling into a campground anyway. My fresh tank will auto fill while hooked up to "city" water... we run all fresh water thru our filters now and the filters really knock down the water pressure so we just fill the fresh tank and pump from that. We can dump grey/black while in campgrounds or at dump stations. I'm using 18 gallon grey/black tanks now. They are good for about 3 or 4 days. We will probably not ever need to stay more than 1 week with out being able to dump tanks... but I still have my old tote tank (need to get the four wheeled kind... easier on my back). I can make several trips if need be.

[lornaschinske]

To be honest, I've never worried about my TANKS freezing... it's all the valves & piping that will freeze. And it's such a joy to have those crappy RV dump valves freeze shut. But then we were never at a place where it would freeze longer than a day or two. And overnight freeze won't cause much damage if you are set up for it. For that even pipe insulation will often prevent the pipes from freezing. It's the fittings you have to worry about, especially if you have any of the metal ones. We found the metal parts of our water system froze up long before the plastic parts. Don't forget that pipe insulation will also prevent the pipe/hose from thawing as well once it freezes. We stayed in our popup thru a Chattanooga winter one year. That meant we got freezing temps at night but it warmed up during the day to well above freezing. My water only froze up at the city inlet valve on the popup (metal-to-metal connection) and at the hose bibb (also a metal-to-metal connection). My water hose generally started freezing at the "cold" spot of the metal connections than froze from that point back. I had no holding tanks to worry about in the pop-up. The easiest way to keep potentially keep your pipes from freezing is to run (110VAC) heater pipe tape on your pipes (including all connections) and insulate the pipes. Put the heat tape on a switched outlet. Use (110VAC) water bed heat pads under your tanks and insulate them. Set the thermostat to a low setting (it will melt the foam insulation at bit if it gets too hot so keep it low) and put the heat pad on a switched outlet. Keep your dump valves warm! An insulated box with a standard incandescent light bulb will work (that's how we always kept the water pump in our spring house warm thru the winter at home). But the absolute best way that we have found to keep your pipes & tanks from freezing is to be far enough south that you are never in freezing weather!!

[Locutus]

Originally Posted by bender477

when traveling a good dilution of pink rv antifreeze in the tanks will not freeze solid , but turn "slushy".

Rock salt is cheaper. Wash about a cup of rock salt down the kitchen or shower drain, and dump another cup down the toilet (if you have separate grey and black tanks). This will lower the freezing temperature of the wastewater.