Control Your Water Heater or A/C with INSTEON/X10
EZSwitch30 30A INSTEON X10 Controller allows to control your air conditions or water heater using X10 or INSTEON commands. The module has built-in memory to trigger events on the outputs to last for 1 to 255 minutes. But the most interesting way is to control the EZSwitch30 using special software such LinuxMCE (currently for X10 only). In case of fault the control system it’s possible to operate with device by pressing the set button on the side of the EZSwitch30.
The EZSwitch30 is available at price $114.99.

Interesting device to control water heater. Does it helps to save cost?