The GREEN YACHTING standard Isotherm kit is available in 12, 24, and 48v versions. It comprises
 
	
Our intelligent controller that constantly monitors the state of your batteries and the temperature of the water in your boiler. If they are at least 80% charged, the electricity from your solar panels is in effect diverted to your water heater if the temperature is under 43°C. It cuts off at 52°C.
	
A 12/24/, or 48v replacement 300w heating element
 
You can add a remote panel to the basic kit.