I would like to hear anyones opinion on a good heat load calculatiion software. I am at a point where I could go into buisness for myself, but do not have the time to go back to school to learn man j /d . I have 7 yrs in the buisness and mainly do change outs. I am a Firefighter and really just want to use hvac work as a supplemental income, however I want my work to be A PLUS, as I have always been taught to do the best job I can. Thank you for any advice!