Cold Enough To Freeze Your Winnebago

This Christmas found us taking Muddlin’ Through back to the midwest for the holidays. The trip out went really well.
Driving was a pleasure, the scenery was great, and we stayed in a couple decent RV parks. One was actually quite nice – the USA RV Park in Gallup New Mexico. Friendly staff and nice level pull-through spots.

As we got further east, and further north, things became less smooth. The cold was starting to make its presence known. Two of our tire sensors stopped reporting. We were pretty sure this was just the year-old batteries not having sufficient remaining capacity at the low temperatues we were encountering. (This was later confirmed when we replaced the batteries and all was well.)

At one point I noticed the black tank had started reading as “Full”. I doubted that, but was cautious anyway – if there is one thing I never want to experience, it is an overflow of the black tank!

Here I should recap. Last year, we picked up our RV at Licthsinn in northern Iowa and spent a week or so running around in some of the surrounding states. Winter to be sure, and the Paseo handled it well. The Truma kept everything nice and warm even when just running on electricity.

Ok, now back to _this_ year. A different year altogether. It was cold last year, but nothing compared to this year. While the core temperatue in the RV was reasonable (between 60 and 70), the edges were beginning to get a bit too cold…

By the time we realized that we were not going to be able to keep things warm enough, we were already in trouble. Ok, we weren’t, but the Paseo was. Things were starting to freeze. We purchased a lot of RV system antifreeze and attempted to do a partial winterization, but alas once some lines are frozen, that’s no longer an option. And lines were frozen.

By judicious application of our hairdryer, we thawed the water tank drain and emptied all of the non-frozen water, which was most of it. We were also able to get antifreeze to at least the galley sink cold-water line, but that’s as far as we got.

So at that point all we could do is let things freeze (or in many cases, stay frozen). The interior core temperature never got below about 35 degrees, but at the edges it was as cold as 15 or 20.

On electricity it appears that the Truma was able to mainain a 30 to 35 degree differential between ambient and internal air temperature. Plenty if the ambient is, say, 25 degrees. Not enough when the ambient hits zero or a few degrees below.

A few days passed, and it was time to head home.

Once we had gotten to warmer temperatures, the black tank started reading properly, as expected 1/3. My guess is that some water had sloshed up and frozen on the tank right where the sensors read.

Once back in San Diego, it was time to assess the damage. With everything thawed, and the water pump switched back to draw from the tank, we hit the pump switch. The pump ran, and it was obvious that something was leaking since it ran longer than required to pressurize the lines. First leak – the outlet for the outside spray hose at the back of the passenger side bench. Upon removing the connector, the fitting had obvious cracks.

Since that is flexible hose, I was able to bend it over and hold it crimped with vice-grips. It still weeped a bit, but was sealed enough to resume testing.

Amazingly, that appears to be the only issue! Everything else seems to have either been kept just warm enough, had little enough water, or was flexible enough to come through ok.
The fact that Pex tubing has enough flex to not burst when it freezes was undoubtedly a huge factor.

The Truma was protected by the fact that the heat was on full time.

So between a little emergency winterizing, the Truma running 24/7, and a lot of luck I think we learned a good lesson quite cheaply.

Seriously hoping that although further trips may see freezing temperatures for a brief period (e.g. overnight in the desert), that we have done our last foray into days of time in conditions hovering around zero!

What We Did Right

  • Filled the pump with RV antifreeze, and as much of the cold water lines as we could.
  • Kept the Truma running (on electricity).
  • Opened up the benches, drawers, and cabinet doors to get as much warmth to the plumbing as possible.
  • Kept the tank heaters on.
  • Opened faucets and bled as much pressure and water from the lines as possible.

What We Did Wrong

  • Did not anticipate just how cold it was going to get, and how long it was going to stay that cold.
  • We should have winterized as much as possible much earlier in our trip. There was probably a point where we had already enjoyed the full use of the RV and could have winterized while it was still warm enough to do so completely before continuing our trip.
  • Forgot to remove the under-sink water filter before running antifreeze through it. Doh! Oh well, we had planned to replace it after this trip anyway, but still a bonehead move.
  • Did not deal with things before we were both fatigued and hurried.  That led to things like the water filter mistake.
  • Left San Diego.  😉



Author: Don Meyer

An average guy trapped on the surface of a sphere who enjoys SF, programming, sailing, Legos, and many other nerdy pursuits.

2 thoughts on “Cold Enough To Freeze Your Winnebago”

  1. Great article. So we are I. San Diego going into the mountains of Uta with temps in the 20. We purchase our paseo a few month ago and need help desperately how to winterize but maybe still use the toilet Any info to guide us in the right directions would help. Thanks so much.


    1. Thanks! Our main issue was the water lines and the fresh water tank not getting enough heat since they are in areas that don’t have enough insulation and don’t have enough of the warm airflow that the main part of the interior gets from the Truma.

      Freezing or just below wasn’t a big deal for us, but low 20s is where you need to take extra precautions. And don’t try to dump your tanks when it’s freezing – the tank heaters might help the tanks themselves, but the drain plumbing has nothing keeping it warm!

      Sadly, we sold our Paseo a while back, so no new cold weather experiences to relate.

      Good luck!


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s