Troubleshooting and diagnostics

This is a collection of information that we can not take credit for and we can not guarantee the accuracy of the older data. This has proven to be helpful to us for many years and we do not know the original author. https://www.nachi.org/forum/f20/hvac-manufacture-dates-174/ HVAC AGE CODES IN SERIAL # INFO Amana: BLACKHORSE. B=1971 or…