Thermostat Wiring Diagram Color. The color of wire r is usually red and c is black. The basic heat ac system thermostat typically utilizes only 5 terminals.
13 rows thermostat terminal designations quick guide detail wiring color guide below. Thermostat wiring color codes thermostat black or blue wire c wire thermostat red wire r or rc wire thermostat white wire w1 or w2 wire orange wire for o and dark blue wire for b ob wire thermostat green wire g wire yellow thermostat wire y1 and y2 wire other wires bk rs1 rs2 odt1 odt2 aux no aux c aux nc. Well explained tutorial on wire color codes.
I just bought a new digital honeywell thermostat th i am replacing an old mercury one the writing in the back is janitrol hpt thermostat wiring colors.
With the top thermostat wiring diagram showing an air conditioning system. One is for cool and the other is for heat hence the abbreviation rh and rc. This type of wiring requires a line voltage thermostat and is not compatible with low voltage thermostats. These two connections will ensure that there is power to the thermostat that you are.