Thermostat wire color standards

[kmcgaugh]

Thermostat design has changed to digital over the last 20 years.  The wiring of digital thermostats requires a red power and a common wire.  The common wire color is not standardized.  I would like to promote the BLUE wire as the common.  WHY?  Thermostat Cables of 5 wires or more always have a blue wire which is not needed for a standard heat and A/C system.  We always use it in digital upgrades because a 5 wire thermostat cable is the most common in homes older than 20 years.  The next most common cable is 6 which adds brown, 8 which adds orange and black, 10 which adds pink and gray.  The 24V hot and common will short out the transformer within seconds if not wired correctly.  So the need for a standard is urgent!  The blue wire is the most common, cheep, and a simple fix if we all agree to use it for the 24V common.  kmcgaugh