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WyCamper's avatar
WyCamper
Explorer
Dec 12, 2013

RV Anti-Freeze Freezes

Just discovered that undiluted Supertech RV antifreeze, rated for -50F and sold at Wal-Mart, freezes solid at MINUS 2F!! I have 6 gallons of undiluted SuperTech in my 2010 5th wheel currently. Went out a few days ago to check that my toilet seal was holding antifreeze and found it frozen solid. Took pic with box of matches set on it. Bought another gallon at Walmart this week and set it out, unopened, two nights at below zero. Took another pic of it frozen solid this morning at Minus 2F. Getting the run-around from Wal-Mart, all they want to do is give me replacement product...they are missing the point. SUPERTECH should be pulled from the shelves and change their advertised rating of "-50F".

49 Replies

  • Nothing wrong with the RV antifreeze it is working as it should. Also that is why we blow out all our lines with air, we use our RV all year. One advantage of living in the south it only freezes for a hour or two a day and I do not want to wait for the antifreeze to thaw so we can use the RV water system.
  • Perfectly normal like mentioned above. Happens every winter to us and never had a problem yet
  • According to Dow (I can’t find the e-mail now)

    Propylene glycol antifreezes are designed to provide burst protection to temperatures of -50° F…
    Ice crystals will start to form in -50 RV Antifreeze at temperatures around +10° F, and it will appear to be solid ice at around -10° F to -15° F.

    Propylene glycol based antifreezes continue to contract and will not expand until temperatures of -50° F are reached, thus providing burst protection for pipes…

    Call antifreeze mfg. and report it and ask, if in doubt…
  • None of the RV antifreeze products remain in their liquid form. This is proven by the fact that it will freeze and makes slush cubes in the ice maker. If it did not freeze and got into your ice maker it would never work its way through when you flush the system out. It is designed to not freeze solid and does not expand saving your plumbing.
  • All antifreeze will turn to slush, don't care how cold it gets.
  • Downtheroad is right it does not expand like water so it will not cause any damage
  • But, did it expand? (like water does when it freezes)
    If not, it can solidify all it wants and it will cause no damage.

    And, welcome to the Forum - your first post.

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