Common split systems use varying refrigerants, in a range of quantities and leakage rates. These systems can have a hard time meeting the threshold for credit compliance because their leakage rates are high. Check your specifications early in the design stage and investigate these products if you’re thinking of using split systems.
Packaged terminal air conditioners (PTACs) typically use refrigerants with a high environmental impact. These units may make meeting the credit requirements more challenging, especially for hotels and multifamily residential projects, which tend to use them. The industry has been moving toward upgrading these refrigerants, so check with manufacturers for recent upgrades to their products. Newer refrigerants may help credit calculations.
R-410A is a common replacement for R-22 as it is more environmentally benign, with similar performance. It can help with compliance, depending on the equipment variables of “coolant charge to cooling capacity” ratio.
Even one piece of equipment can tip your calculations to compliance or noncompliance. Use the calculator in the LEED Online credit form to run calculations from the beginning of HVAC system selection (note that your project has to be registered through LEED Online to download those forms). This gives a sense of how far from compliance a system may be; teams then get a better idea of how significant a change may be required. Note that annual leakage and end-of-life refrigerant loss rates are set to defaults but can be edited if needed.
Core and Shell projects include all equipment within the project scope and LEED boundary. For example, this may include AC systems in common areas and heat pumps in tenant spaces.
If your project building is connected to a district chilled-water system, you have to include all the chillers in that system in the calculations, even if they are outside your project’s scope or control.
All permanently installed HVAC&R equipment with more than 0.5 lbs of refrigerant—including chillers; unitary HVAC equipment (split and packaged); room and window air-conditioners; computer, data center, and telecom room cooling units; and commercial refrigeration equipment—is addressed by this credit.
If your building uses only natural ventilation, it complies with Option 1 and the credit is automatically earned without your having to submit any calculations.
The calculations are based on the rated power of each appliance or piece of equipment. So a single large power-using appliance, like a refrigerator, may have a higher rated power than dozens of computer monitors. Investigate if those large appliances are Energy Star-labeled, especially if they are to be purchased new for the project, to increase the project’s percentage of rated power that is Energy Star-labeled.
