IS this in your 1998 HR?
IF it is then you will have separate t-stats for the electric element.........located on backside of tank where electric element is.
The 120V AC power goes directly to element thru t-stats so problem could be bad connection on t-stats, bad t-stat or bad element.
Need to check for 120V power at/thru t-stats and at element.....caution!!!
(In 2004 Atwood combined the electric/propane separate t-stats into one set of t-stats and the 120V AC power to electric element is controlled by DC relay)