Carmel Software announced that it has released an upgrade to its popular residential HVAC load calculation software program: Residential Version 5.0. Residential 5.0 is a residential and light commercial HVAC load calculation software package based upon the ASHRAE 2001 Fundamentals residential algorithms (Chapter 28). It is designed to provide the user with total cooling and heating loads for a building so that they may properly specify the correct size HVAC equipment (whether it is a packaged rooftop unit or a furnace).