Never tried it.I have an existing standard 40 gallon electric water heater and I want to convert it to solar if its possible?
Cool ideas for hot water. I had not thought of using just one of the heating elements. Checking my Whirlpool the two elements are each 4500W but it seems they are never used simultaneously as the total rating is 4500W. A full 4KW water heater would overload my system. Running at 120VAC would cut the power by 75% to about 1250W. That is doable but still 10A (not 20A). Heating much slower of course. What controller is your friend using?The heating elements must be electrically isolated from the grid. Often just the lower element in a tank is connected to PV. There are three phase elements which can replace factory ones. One element is still connected to the grid and the other two to PV. An additional thermostat has to be added for the PV. Going full safety really complicates wiring. I have a friend with grid tie system, and he operates his controller right off the panels. Not only that his dryer heating element is also connected. When he turns on his dryer, the controller switches from water heating to clothes drying automatically. This is advanced stuff. He even charges his car from PV without going thru grid tie. Florida lots of sun. I'm off grid and my water heater switches to the dishwasher when running.
There has been some bad reviews of that place in past and what they sell.These guys have you covered. Including DC thermostat control.
DC Water Heater Elements | Missouri Wind and Solar
Choose from a wide variety of submersible DC water heating elements for direct connection to your batteries or solar panels. Great for RVs, heating stock tanks, or converting your AC water heater. Don't forget to add a thermostat.windandsolar.com
Good to know!There has been some bad reviews of that place in past and what they sell.