Hi James,

The load calculation is all about determining the peak cooling load that will cover 99% of the time. Peak load typically occurs in the early evening on design day, not at night. Therefore, ACCA Manual J methodology advises that occupants should be placed in the room that they will most likely congregate in during the early evening. This is why we add occupants to the living room instead of the bedrooms. ACCA also recommends determining occupants based on the number of bedrooms + 1 (assuming the master bedroom is occupied by two people) as opposed to the actual quantity of people that live in the home.

For appliances, you also want to only account for appliances that would be running at the same time in the early evening. This would typically be a fridge (or any other appliance that never shuts off), as well as a dishwasher, load of laundry, and some ancillary lighting and televisions. We do not recommend including all lights and appliances found in the home as this will lead to an overstated load. 

When performing a block load, you can select from one of the appliance lighting allowance options which cover common scenarios. When performing a room-by-room calculation, appliances and occupants are automatically added based on the "room type" you select for that room. If you prefer to add your appliances and occupants manually, simply select "Other" as the room type and then use the internal loads tab to add your appliances and occupants.

Best Regards

Bill