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Room Loads vs. System Loads

Posted on October 7th, 2011. Last updated on November 1st, 2018.

Design Master HVAC calculates two total load values for spaces: room load and system load.

The room load is the load that is seen inside the room. This load needs to be accounted for by the air being supplied to the room.

The system load is the load that is seen at the air handler. This is the total load that the air handler needs to account for.

The system load includes the ventilation load and the plenum load. The room load does not include these two values.

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