If the simulation tool requires the use of energy efficiency ratio (EER) instead of seasonal energy efficiency ratio (SEER) for a heat pump or air conditioner, then the EER for the Benchmark shall be calculated using Equation 4. If the actual EER for the Prototype is not readily available, Equation 4 may also be used to make an approximate conversion from SEER to EER (Wassmer 2003):
EER = -0.02 × SEER2 + 1.12 × SEER
Heating and cooling equipment (including the air handler) shall be sized using the procedures published by the Air Conditioning Contractors of America (ACCA). (See http://www.acca.org/store/category.php?cid=1.)
The Benchmark shall not have a whole-house fan.
If the Prototype actively controls relative humidity, then the Benchmark shall include a stand-alone dehumidifier with an energy factor of 1.1 l/kWh (EPA 2006). Sensible heat generated by the dehumidifier shall be added to the cooling load.
The Benchmark air handler shall have power consumption equal to 0.00055 kW/cfm.
The Benchmark shall include an air distribution system with the properties listed in Table 6. The location of the ductwork in the Benchmark is based on the type of foundation used for the Prototype. If the simulation tool does not permit the input of duct specifications to the level of detail used in Table 6, then two values (one for heating, one for cooling) of seasonal distribution system efficiency (DSE) shall be estimated and applied to the heating and cooling system efficiencies to represent typical losses from ducts. The DSE values shall be determined using Table 6 and the procedures in the Draft American Society of Heating, Refrigeration and Air- Conditioning Engineers (ASHRAE) Standard 152P (ASHRAE 2001b). A spreadsheet developed by Lawrence Berkeley National Laboratory (LBNL) has been modified by NREL and integrated into the Building America Analysis Spreadsheet (http://www1.eere.energy.gov/buildings/ building_america/perf_analysis.html) to assist with this calculation.