Ductwork air leakage is a major contributor to energy wastage. It has been identified as an area in need of attention by the newly released HVAC Optimisation Guide.
The new business guide aims to assist facility managers and building owners to maximise the energy efficiency of their heating, ventilation and airconditioning (HVAC) systems.
Developed by the NSW Office of Environment and Heritage in partnership with the Australian Institute of Refrigeration, Air Conditioning and Heating (AIRAH), the guide outlines 20 HVAC optimisation strategies and how they can be applied to the vast majority of commercial systems, both in older and modern buildings.
HVAC can be a significant contributor to business energy use and operating costs, typically consuming the largest proportion of energy in commercial buildings.
But unlike other more costly energy-efficiency strategies, HVAC optimisation does not typically require much capital to implement as it focuses on the best use of existing systems rather than large-scale equipment upgrades and replacements.
“Ductwork air leakage is an important issue when assessing HVAC due to its potential energy wastage and impact on system performance,” the guide explains.
“When a system has to compensate for ductwork leakage, it requires increased air flows and fan power consumption. Leakage into and out of ductwork increases system heating/cooling loads and can impact on Indoor Air Quality (IAQ).
“Identifying and repairing ductwork leaks to ensure adequate sealing is an important step to optimise HVAC performance. A number of sealant types, such as liquid sealants, mastics, tapes or heat-applied materials can be used.
“Ducts can be manufactured to incorporate self-sealing factory-applied gaskets. Retrofitting sealant to fix leaking ductwork is difficult and, as such, all new duct work should be sealed and tested.”
All new ductwork for air distribution systems greater than 3 m³/s should be tested for leakage in accordance with AS 4254.2.
OEH has a panel of specialists who will be able to assist with any optimisation project.
Visit www.environment.nsw.gov.au/business/energy-efficiency-expert.htm.