I've seen this question many times...and faced it myself once before... and am looking at it again. The refer won't drain batteries in the situation she is describing... she plans to run from here to there without the refer energized...and plug in when they get there.
I found an amish company online that makes new amonia absorbtion coils to repair the dometic... they don't even want your old one in exchange... the repaired cores usually fail again prematurely. ..
That is how I fixed the one...I am deciding between the same avenue or full replacement on another...
Friends who are happy with the dorm unit in their situation have suggested the same to me... all you do is cap the propane line... and run on shore power at locations... once the dometic is removed you have a huge place to position the dorm unit... some trim work will be desired...you may also want to cover up the side panel where you now acces the rear of the dometic as it will be gone...bugs, wind, rain...this is not acceptable to me as I like to run the propane between stops... and often find myself at a lake or extreme rural area with no shore power and thus require the gas option as I do not have batteries to support an invertor either...
