Learned the trade in the USAF, retired in 94. ( yea, there was a HVAC rate )
Spent the last 15 years in the midwest as a boiler operator for an Ethanol plant.
EPA 608 Universal in 95.
Now I'm working at a medical college as a HVAC tech here in the south, and this old brain might need some refreshing on the AC side of the house.
Thanks for letting me join in.
( User name comes from operating a 2 drum, bent tube, 80 kpph, coal fired Zurn boiler )