Wiring most thermostats is done in the same manner with minor exceptions depending on the brand and what the specific unit was designed to do. Ruud manufactures many different series of thermostats that are designed to handle different types of climate control systems utilizing the appropriate wiring to operate correctly. Install the correct thermostat for your climate control system by connecting the color coded wires coming out of the wall into the appropriate terminal connectors.
Turn off the power at the breaker box. Inspect the thermostats terminal designations and identify each terminal. Follow the directions for your thermostat provided by the manufacturer.
Attach the red wire into the terminal connection marked R. This leads from a transformer and provides power to the thermostat.
The yellow wire is connected into the Y terminal and controls the air conditioning. This wire runs to the compressor relay.
The white wire is connected to the W terminal. This wire goes straight to the furnace or other heating source and controls the heating system.
The green wire is connected to the G terminal. This wire controls the fan relay and powers the blower fan to circulate the air throughout the system.
The black wire is attached to the C terminal. This terminal completes the 24 volt circuit necessary to power most hard wired digital thermometers.
The dark blue wire is attached to the Ruuds' B terminal for systems utilizing a heat pump. This powers a reversing valve when it is in heat mode.