Frozen antifreeze

[Jerryg]

This fall, I bought 4 gallons of RV antifreeze to winterize my RV. I used 2 to do the winterizing and put the other 2 in the underbelly storage. This week, we had a cold snap up here in Minneapolis and while I was packing the rv for a trip south, I noticed that the 2 extra gallons were frozen solid so the bottoms of the containers were bulging. The temp outside at the time was -13F. The antifreeze is guaranteed to provide burst proof protection to -50F. I contacted the mfgr and they said it is common for it to freeze at about 10 degrees above zero but will still provide burst protection to -50F. Can anyone explain that to me? The containers were frozen hard and bulging so why wouldn't that be a problem for a rv water system?
Thanks

[Jerryg]

This fall, I bought 4 gallons of RV antifreeze to winterize my RV. I used 2 to do the winterizing and put the other 2 in the underbelly storage. This week, we had a cold snap up here in Minneapolis and while I was packing the rv for a trip south, I noticed that the 2 extra gallons were frozen solid so the bottoms of the containers were bulging. The temp outside at the time was -13F. The antifreeze is guaranteed to provide burst proof protection to -50F. I contacted the mfgr and they said it is common for it to freeze at about 10 degrees above zero but will still provide burst protection to -50F. Can anyone explain that to me? The containers were frozen hard and bulging so why wouldn't that be a problem for a rv water system?
Thanks

[rjf7g]

Hmmmm...sounds like it is just pink water to me. What brand is it? I did read somewhere about someone buying several gallons of what turned out to be pink water. Now, the person buys only Prestone and "freezer tests" each gallon.

[Jerryg]

The brand name is Splash. Are you saying that the person refering to the "pink water" had a similar problem?

[rjf7g]

Yes. As I recall from the post, he came home from a trip knowing he was going to have to winterize and he found his antifreeze frozen and expanded. Everything but water contracts when it freezes, so he became suspicious. He bought a gallon of Prestone and stuck it in his freezer for 24 hours and found that it didn't freeze. I can't remember what forum this is from, but perhaps someone here has had a similar experience.

[DonavonP]

Hi Jerry, I'm just west of you and have noticed this for several years with different brands. So far I've had no problems with bursting.

The current gallon is RV Plus I think I bought at Menards (can't remember) and it's slightly bulged. If it were a gallon of water, the plastic bottle would have a rip in it.

[Jerryg]

yes, I talked to my dealer. He said it is normal. It will freeze but won't expand and break anything.

[Harleygirl]

I was wondering if i can put antifreeze in my holding tanks while i am using my rv to prevent freezing until they are emptied each week? I am NW of Ft Worth Texas and we get a few days of temps in the 20's and then warms back up, i have noticed that there is not a bit of insulation or protection of any kind around my holding tanks. any suggestions? my 5th wheel is a 2003 Trail Winds by R-Vision.

[xc-mark]

yes its normal , antifreeze turns to slush about 20* above the freeze solid point . Its the freeze solid point that breaks the pipes .If it a big issue you can go to your local plumbing supply store and get -100* antifreeze and it will stay fluid in the 48 states , maybe not in AK. I run the same stuff in the heating system in the garage so I can turn off the heat in the winter when its not in use. about 3 years ago I couldnt get the heat to work on a -8*F night , pipes where frozen... never burst , I took a sample and put it in the freeze and at +5 it was slush.