Too bad you can't just install another Toro Monitor controller. If temperatures in the valve box are an issue, you could get some relief by digging a much deeper box, and adding an inner divider.
Depending on the current drawn by the solenoids, you could look at using a 5-watt, 20-ohm dropping resistor. Actual power drop in the resistor will be more like one watt, but it doesn't hurt to spec this stuff conservatively.
Last edited by Wet_Boots; 08-02-2010 at 01:18 PM.