Why would my furnace just start blowing out cold air? It doesn't try to light, the blower runs, and there's a small green light that flashes three times today.


The light is providing a code that corresponds with its code chart and says what part failed or failed to read what it is supposed to this narrowing down the possibilities for yourself or a service tech to pinpoint the issue. The blower comes on as a default feature upon failure. This is likely what has the blower running.

Updated on March 1, 2018

Original Article:

How to Diagnose Furnace Problems & Why Red Light Is Blinking
By Dan Robbins