How important is it to renew the Alde fluid?

The Alde glycol question has been an issue for everyone with an Alde since 2014.  Nucamp and Alde have always said "change the glycol every two years". In December of 2020, they changed to the new, improved, much more expensive "Truma Alde" glycol and that is the only "approved" glycol.   That is the entire advice from Alde and NuCamp.  

So, for 12 years, we have been on our own.  The Alde 3010 trailers in the NuCamp trailers and the Airstream trialers wound up with corrosion at the stub ends of unprotected aluminum convectors and parts.  Alde and NuCamp helped with getting us the parts to repair the corrosion, but that was all.  The reason for the Dec 2020 glycol change to the "new, improved" glycol was the only reaction from Alde.  The claim was the new stuff had "better anti-corrosion properties".  There are design changes to the newer Alde hoses and convectors and various hose connections....but, so far, there are still reports of corroded parts on Aldes even with the "new" glycol, and even in trailers less than 2 years old. 

The usage of the trailer has very little to do with whether or not the aluminum parts can corrode.   The focus on all the corrosion issues comes down to how the convectors and parts were clamped: poor clamping allowed the glycol to seep under various hoses, rest against the exposed (uncoated) aluminum parts, and corrode.  Once these parts were isolated from the "anti-corrosion chemicals" in the glycol, nothing will stop the corrosion from happening.  So, the amount of time the Alde is actually used probably has little to do with the corrosion issue. 

The "two year" glycol change is what Alde "recommends".  It is hard to say what owners "actually" do.  Many owners have sorted out ways to examine the glycol for the amount of "anti corrosion chemicals" remaining in a sample of glycol and found it still viable at around two years.  Some owners have decided that there is no need to "completely" pump out all the glycol, but do a simple "drain and replace" a gallon or so at a time, which, in theory, would "replenish" the anti corrosion chemicals in the glycol.  (These chemicals make up only about 5 percent of the glycol mix).  After a couple of "drain and replace" cycles, the glycol would be completely "changed" without going through what can be an expensive process for owners who do not want to change their own glycol. 

So, my two cents, at least.  This group (and others) have literally written an encyclopedia about the Alde, the glycol, the glycol change, the corrosion issue, etc.  We owe the owners who worked so hard on "how to change the glycol" and "how to clean the corrosion" a great debt.  They have saved many owners a ton of expense, and probably saved many Aldes, also.