Welcome to RV.net.  I'd encourage you to read the forum, sadly you're not alone with some issues with their Voltage units.
However, most RV warranties are based on time not use.  This happens often when a unit is purchased in the fall and may sit, unused, all winter long.  If you have documentation from the dealer showing you've been working on the issues that may help you, but if you are just now bringing items up after the warranty you'll be hard pressed to get them to repair it after the warranty expired. 
Over my time here on the forums one thing I learned was while under warranty get it in for service and inspection of the problem right away.  Provide your dealer a list of problems, in writing, and ask each to be addressed and resolved.  Keep your dealers intake paperwork, then make sure they address each issue, showing in writing how it was resolved or if not why not.