So your Manual J Load Calculation was just rejected because it wasn’t “ACCA Certified” – What load calculation software should you have used?

It is critical your Manual J load analysis is produced with ACCA certified software by someone who understands Manual J theory – not just someone who can punch buttons in a software program. Ask your HVAC designer if they have read the ACCA Manual J (8th Edition), Manual S, Manual D & Manual T books and if they are certified designers in the software they use.

ACCA (Air Conditioning Contractors of America) released its Manual J load calculation procedure in 1986.  ACCA wanted to develop an accurate calculation method that not only saved time but improved the quality of systems selected and duct work installed.

In 1985 at the Massachusetts Institute of Technology (MIT), Bill Wright was giving a graduate seminar on heating, ventilation, and air conditioning (HVAC) when he was approached by the Air Conditioning Contractors of America (ACCA). The largest organization of HVAC contractors in the United States, the ACCA wanted to work with Wright to develop a software program to run calculations for HVAC designers. And, so, WrightSoft was born. Still the leader in HVAC design software, it now produces many software programs to aid in HVAC design. But its first product, a Manual J load calculator, is still its flagship product. If you want to calculate a load using Manual J, then it’s your best bet to look for a WrightSoft Manual J compliant designer.

This software program became known as Right-J, and it was the beginning of a line of software programs that became more advanced over time.

In order to become a WrightSoft Manual J designer, candidates must undergo rigorous training. They must not only learn how to use WrightSoft programs themselves, but they must also learn how to clearly explain these programs and their use to others. This is because it’s of vital importance not only for the designer to understand his own design, but also for the contractor to understand what the design is intending to accomplish and why. That way, he’s not just a robot following a plan, but a human being with common sense who can recognize when something in the plan is awry.

In addition, WrightSoft has WrightSoft University online 24/7 which we have every one of our designers go through before beginning their first project with us.  And the WrightSoft technical staff is very easy to work with and have solved every issue we have encountered quickly and professionally.  We have been producing ACCA certified WrightSoft HVAC designs since 2005 and have completed thousands of projects with a 100% PASS rate!