Winterizing - how do I know that the Alde tank is drained?

mggielow

This is my first time attempting to winterize our 2018 320S.  I've followed all the helpful advice from this forum, but I question the reason for bypassing the Alde when filling the lines with antifreeze.  It seems to me that any residual water in the tank could freeze and cause a mess, so why wouldn't I add antifreeze to the tank?  I did drain the tank according to the procedures (open yellow valve, raise and lowered the trailer), but how can I be sure there's no water in there?? 

pthomas745

The Alde tank holds only about 2 1/2 gallons of water.  The tank is drained by the yellow valve and the cold water low point drain.  As long as "most" of the water is out of the tank, there won't be enough water left to do any damage. 

RTWCTS

The reason you bypass the Alde when adding antifreeze is that it is corrosive to components of the system.

Sharon_is_SAM

If you are not going to use the Alde while winterized, antifreeze will not hurt it.  As pthomas noted, a little water left inside won’t hurt.  To enhance draining the tank, it may help to open a hot tap (prevents a vacuum effect).

RTWCTS

Sharon_is_SAM said:

If you are not going to use the Alde while winterized, antifreeze will not hurt it.

Sorry everyone about giving incorrect information in my previous post in this discussion.

ScottG

It's worth noting that the Alde bypass serves two functions. It's also used to prevent getting bleach solution in the HW tank while sanitizing. Allegedly, bleach can be corrosive to stainless steel, so should not be left in contact with the tank liner for extended periods.

mggielow

Many thanks to all for the helpful replies!  I feel better about it now.  Should also note that when I first picked up the trailer, I made the rookie mistake of sanitizing the HW tank... hopefully that one time mistake won't come back to haunt me...

pthomas745

The Alde tank is legendary for being the "precious snowflake" of the trailer.  The good news is, the Alde tank is plenty robust, and with ordinary care, it seems to survive all our attempts to bleach it, antifreeze it, etc.  There have been some leaks and failures, of course, but it doesn't seem any of them had anything to do with bleach of antifreeze. 

@RTWCTS the idea on "no antifreeze" in the Alde tank goes back to conversations about "whether the antifreeze in the Alde tank could boil or not".  Which is an internet rabbit hole of epic proportions.

Bleach can damage stainless steel, which is what the Alde tank is made of.  (How long it would take and what concentrations of bleach is another huge rabbit hole).  Trying to isolate getting bleach in the Alde is a good practice.  RV antifreeze is "propylene glycol", which is used in many consumer products, food, etc.  Probably would have zero effect on a stainless steel tank. But, again, it is just considered a good practice to isolate the Alde from anything that isn't water.

Here is a thread with a video from Paul Chamberlain interviewing a tech from Alde.  From back when Alde actually communicated like a good corporate citizen.  Interesting video, and interesting comments in the thread.

https://tab-rv.vanillacommunity.com/discussion/14336/unapproved-winterizing-the-alde-3020-in-a-2021-tab-320s

RTWCTS

Thanks for helping to (re)educate me on winterizing with anti-freeze @pthomas745. Honestly I used that method once, in 2018, the first year we had our 320. Ever since we've just blown everything on the supply side out with air to winterize. Being within a stone's throw of the ocean, we really don't get hard freezes here in southern VA. Guess I shouldn't have chimed in earlier...

Sharon_is_SAM

@RTWCTS - per the Alde techs at uCamp:  If you choose to use antifreeze in the Alde and heat your cabin while winterized, you must make sure the Alde AF tolerates the high temperatures of the Alde.  Otherwise, it can degrade and not provide the necessary corrosion protection.  But, if you will not use the Alde, then it’s all good with adding x brand AF.

pthomas745

@RTWCTS these are always good conversations.  New owners flow in all the time, and the discussions and ideas are always useful.

bergger

Yes they are good conversations.  And these conversations help educate the new owners that there is often several good methods of doing things all with good results.   With winterization and glycol changes being good examples of that.   As far as winterizing goes the compressed air method is used by many people and can work very well, especially in a climate like you are in @RTWCTS.  The antifreeze method, using -100 antifreeze, works well for me where I have to winterize late September or early October.  We just got 15" of snow this weekend and it was -7 this morning.  While I do love living where I do I sometimes get jealous of people who can use their trailers year round!  

RTWCTS

We love visiting areas like Leadville in the summer @bergger to escape the heat and humidity around here. As I read once somewhere 'Try to get to higher Latitude or altitude...'. By contrast it is 83 degrees here today. Our last gasp of warm weather, I fear.

ScottG

mggielow said:

Many thanks to all for the helpful replies!  I feel better about it now.  Should also note that when I first picked up the trailer, I made the rookie mistake of sanitizing the HW tank... hopefully that one time mistake won't come back to haunt me...

@mggielow, I did the same thing. In addition--thanks to the vague instructions available at the time (which I didn't read very carefully anyway)--I used waaaaay to much bleach. Although it took me a month to get the bleach smell out of the system, my Alde has been fine for nine seasons and counting. I wouldn't lose much sleep over it!  :-) 

mggielow

ScottG said: I did the same thing. In addition--thanks to the vague instructions available at the time (which I didn't read very carefully anyway)--I used waaaaay too much bleach. Although it took me a month to get the bleach smell out of the system, my Alde has been fine for nine seasons and counting. I wouldn't lose much sleep over it!  :-) 

Thank you for the reassurance and sense of relief! I also misread the vague instructions and used far too much bleach. So much to learn...