Caleffi has introduced its iSolar 257 series multi-functional temperature differential controller, which can be used for a wide variety of applications and has inputs for four sensors.
Preset factory defaults control a standard solar water heating system, with a second relay (on some models) to divert surplus heat. The auxiliary relay can maintain tank temperature, protect the system from overheating or direct another source to heat the storage tank. Also, a built-in energy meter records solar hot water energy production.
The iSolar 257 is available in four different models that feature easy-to-use icons on a large LCD display to assist users in operating and customizing a solar heating system.
Caleffi: (414) 238-2360