C.A.P. CGC-1 Complete Greenhouse Controller 

The CGC-1 Complete Greenhouse Controller controls all of the main devices required in today's modern hydroponic garden. Your garden's HID lights are controlled by a precision 24-hour time clock. Two outlets are provided for your lights. 

Other functions such as supplemental CO2 and hydroponic pumps are also coordinated with the time clock. Two of the outlets on the CGC-1 are for your exhaust fans or air conditioner.

A built-in thermostat and humistat handle the growing area's temperature and humidity control functions. The two pump outlets allow your water pumps to be controlled by the built in Adjustable Recycling Timer.

A selector switch allows the user to determine if the hydroponic pumps are to cycle only when the lights are ON or 24 hours a day. An auxiliary NIGHT outlet is activated when the lights are turned off.

Supplemental CO2 is coordinated to work in harmony with your exhaust fan's temperature and humidity control functions. When the exhaust fans are running, the CO2 outlet is disabled to conserve CO2.

More info from the Manufacturer (PDF format - Lots of detail.)