ACCA Manual J – HVAC LOADS CALCULATIONS
Before any upgrade in your home, renovation or new construction project , it is ideal to estimate the specific characteristics for your HVAC equipment. Under sizing or oversizing it may cause your discomfort.
The days of using a “rule of thumb” approach to guess the size of an HVAC system is the main reason for experiencing problems at installation and during operations of new equipment. The Air Conditioner Contractors of America (ACCA) Manual J is the approved method of calculating room-by-room and whole-house cooling loads. High-performance homes, and production homes builders find this method as the best way to limit liability and accurately size your HVAC systems.
Residential and Commercial business owners will find this method as one excellent input for initial investment decision.
Calculating cooling loads ( Manual J) is also a mandatory requirement of the 2009 – 2015 International Residential Code (IRC) and International Energy Conservation Code (IECC) to conduct and provide a Manual J, S and D report and to acquire a building permit.
Manual J – Residential Load Calculation
There are dozens of factors and complex calculations to consider for determining the heating and cooling load of a particular home. Your HVAC tech should use the latest software to aid in a Manual J calculation. These are some of the many factors that are considered:
Number, sizes and efficiency of windows
Local climate in regards to average high and low temperatures and humidity
Orientation to the sun
Air-leakage rate of the home
Air-leakage rate of the duct system
Amount and quality of insulation installed
Lighting and heat-generating appliances
Number and ages of occupants
Our trained and certified professionals will help and provides a successful Manual J calculation. Using ACCA-approved methodologies and software, we will work closely with you to gather the necessary construction plans and specifications.
If you have questions or would like to see an example of our ACCA Manual J Building Load Report, do not hesitate to contact us.