Holding tanks frozen. Now what?

[Pete Masterson]

I recall hearing that some of the older WLs had a heat pad under the tanks, presumably thermostat controlled or with an on-off switch. Newer WLs (I'm guessing wide body models) have more insulation and those with AquaHot or Webasto units have a heated basement. (Again, I can't be sure about pre '94 models, but they may have had some means of heating the basement.

My coach, for example, has the dump valves inside the compartment. There is a 2" hole for the water hose and a 5" (or so) hole for the slinky hose to pass through. Both holes have a threaded edge to hold caps (but they were missing when I got my coach). I was able to put together a plug for the 2" hole from some plumbing components, but when I got a pipe cap for the larger hole, the threads didn't work.

The assumption is that the area will remain warm enough (from the heated basement compartments) that it will keep the valves from freezing. However, my experience is that it only takes a little ice to lock up the valves pretty tight. (i.e. I don't believe that the valves and pipe leading to them were fully blocked by ice, only that there was enough ice formed around the valve area that the valve wouldn't move.) The salt trick (whether you use rock, kosher, or table) does seem to work -- at least for temperatures in the high teens (I haven't experienced lower temperatures in my 'bird). 

When I've stayed where there were freezing conditions, I'd keep the basement buttoned up, and I had no trouble dumping so long as I put in a salt treatment after each dump. (The only times I had freezing difficulties was when I wasn't expecting a freeze...) For fresh water, since I didn't want to hassle with heat tape and hose insulation (I wasn't staying that long in those conditions), I'd fill the fresh tank in the afternoon, and we'd use the pump instead of the shore water. Hint: be sure to drain the hose after filling the tank. I forgot, once, and then I had to drag an awkward, frozen icicle-hose inside to thaw it out. I didn't make that mistake twice .

I'm sure that wrapping insulation around the pipes, especially if they're exposed under the coach, would help prevent a freeze up -- after all, the water and other materials entering the tanks are usually well above the freezing point and the insulation will tend to hold the heat inside. The hassle with the electrical to add freeze tape might not be worth it, unless you plan to stay in freezing temperatures for extended periods.

However, the whole point of the RV is that you can move to locations where it doesn't freeze -- which is why we've decided to over-winter at our home in California. (53 today, with 43 expected overnight.)

Pete Masterson

'95 Blue Bird Wanderlodge WBDA 42 (For Sale)

<http://www.aeonix.biz/BBforsale.html>

El Sobrante CA

"aeonix1@mac.com"

On Jan 4, 2009, at 2:10 PM, Ryan Wright wrote:

Thanks for the responses, everyone. I'm going to try the salt with the

5 gallon bucket method first.

Didn't some Wanderlodges come with heated holding tanks? How did this

work - did they route engine coolant through a heat exchanger? Which

years would have had this option available?

This summer, I think I may rebuild my drain system. I'm envisioning

electric dump valves, fully insulated drain pipes wrapped with heat

tape, and a second drain "port" with a fixed/hard mounted macerating

pump. Some extra insulation around the holding tanks, as Ernie did,

etc.

-Ryan

'86 PT-40 8V92