Neil, HamRad is probably right on. Here is a link to a previous discussion by Ozz complete with photo's.
http://www.montanaowners.com/forums/...rchTerms=water
Think it will be of great value to you. A side issue, an hour should be plenty of time for the WH to recover. But one trick I learned on this forum when rapid recoverey is needed. Leave the unit on electric but also flip the switch for gas. Kind of turbo charges the WH. Hope this helps, Jim