AIRAH is poised to release the fourth edition of DA09 Air Conditioning Load Estimation and Psychrometrics, with the official release date set for October 27.

Used to help estimate air conditioning peak loads and partial loads in any given space, DA09 is a fundamental component of AIRAH’s technical manual offering.

“Releasing the fourth edition of DA09 Air Conditioning Load Estimation and Psychrometrics is a significant achievement,” says AIRAH CEO Tony Gleeson, M.AIRAH (pictured above). “Air conditioning plays an essential role in our comfort, health, and productivity. It touches every aspect of our lives. In order to correctly size equipment, peak loads and partial loads for any given space must be known.

“But because it’s not possible to physically measure these loads, they must be estimated. And it is for this purpose that the data and methodology contained in DA09 have been compiled.”

DA09 editor Vince Aherne, F.AIRAH, says DA09 explores the topic of building heating and cooling load estimation in minute detail. Explanations are provided for the psychrometrics of the fundamental air conditioning processes, which are needed to design systems that will provide specified indoor design conditions for a defined range of occupancies and climate profiles.

“Air conditioning load estimation is all about predicting and quantifying the peak heating and cooling loads for a building and facility,” Aherne says. “An accurate load estimation is the first and most critical step in the design and construction supply chain for an air conditioning system. It affects equipment selection, system size and design. It is critical for system functionality, future service satisfaction and energy performance.

“Sometimes more art than science, load estimation aligns the demands of climate, building form and building function with the health, comfort and productivity of the occupants or the process.”

DA09 provides a range of information and design data that can be used in any load estimation calculation.

“The topic of building heating and cooling load estimation is explored in detail in this manual, and the psychrometrics of the fundamental air conditioning processes, which are needed to design systems that will provide specified indoor design conditions for a defined range of occupancies and climate profiles, are explained,” Aherne says.

“Although this is a load-estimation and not an air conditioning design manual, it does draw strong connections between the choices a building/system designer – or load estimator – makes and the magnitude of the cooling and heating loads.”

DA09 covers heat and moisture flow through building elements, solar and transmission loads, internal heat gains from people, lights and equipment, quantifying infiltration and outdoor ventilation impacts, and quantifying system effects. The manual also explains air conditioning process psychrometrics including plotting air states and interpreting psychrometric data for air conditioning system design, selection, and operation criteria.

DA09 is also a source of data and default values for the estimation of internal and external loads on an air conditioning system.

“This application manual is the most comprehensive technical resource available for Australian air conditioning load estimation,” Gleeson says. “It is a must-read reference for anyone interested in the design, selection, installation, operation, maintenance and assessment of buildings or comfort systems, anywhere in Australia.”

The fourth edition of DA09 will be digitally released on Thursday, October 27. Hard copy orders will be dispatched from Tuesday, November 8.

AIRAH members receive exclusive digital access to a wide selection of AIRAH’s technical resources as part of their membership. For more information on AIRAH’s suite of DA Manuals, go to airah.org.au/damanuals