Our 07 Essex hydro hot has worked perfectly for the last 3 ½ years. Generally, had all the hot water we needed only using the AC electrical element. On our last trip, I noticed the water wasn’t getting hot with AC (the overhead switch indicating on, heating status and electric heating element status showing green in the bay). Solution was easy, just used the diesel burner, of course, quickly had hot water.
Back home, doing general maintenance to prepare for our next trip. Used the hydro hot PDF to check the AC heating element. When I opened the electrical box to access the heating element, the pic below is what I found! Wow! Appears the wires grounded and melted most inside. I carefully inspected and replaced all the wires with the proper gage. Used a multimeter to check the Ohms resistance on the heating element (9.2 good). Checked the AC relay (the DC voltage side was good, but there was no continuity on the AC side). Bottom line, besides melted wires, the AC relay was bad. $31.
I erroneously thought the green lights said the AC heating element was good, so I continued to try to use it... this is not the case. These two green lights are just the first step in troubleshooting the heating element. So in the future... when something isn’t working... I’m immediately putting eyes [emoji102] on it!
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Linear Mode
