DOE-2 Reference Manual Version 2.1 - DOE2.com

11. SYSTEM-EQUIPMENTFor the simulation to proceed, the program must know the details of theoperating performance of all equipment. This includes air flow rates(specified in ZONE-AIR and SYSTEM-AIR), control systems (specified inZONE-CONTROL and SYSTEM-CONTROL), and design, as well as off-design, capacityand energy input requirements (specified here in the SYSTEM-EQUIPMENT subcommand).These quantities can either be defaulted or explicitly specified bythe user.If the user is satisfied with the default equipment performance databuilt lnto the program, lt may not be necessary to speclfy any keyword valuesin the SYSTEM-EQUIPMENT subcommand.Equipment operating characteristics arethe design ARI* capacity and consumption aredesign functional relationship is specified.available cooling capacity from a unit is,specified in two parts: first,given; next, the off-design toFor example, the hourlyCAPT = available total cooling capacity = CAP ARI * CAP(WBT,DBT),where CAP(WBT,DBT) is the modifier function to account for off-design WBT andDBT.In keyword form, the equation is expressed asCAPT = COOLING-CAPACITY * COOL-CAP-FT(WBT,DBT),where WBT and DBT are the wet- and dry-bulb temperatures of air entering thecoil for water coils and entering air wet-bulb and outdoor dry-bulb for directexpansion (DX) units.For cooling capacity, it is necessary also to know the sensible part ofthe total capacity. This is, in a similar manner,SCAPT = SCAP ARI * SCAP(WBT,DBT)or in keyword form,SCAPT = COOL-SH-CAP * COOL-SH-FT(WBT,DBT).For all types, SCAPI is not allowed to exceed CAPT' and for DX units,SCAPT is also corrected for entering dry-bulb temperatures other than at theARI rating point (the ARI rating point is: wet-bulb entering = 67°F, dry-bulbentering = 80°F, and dry-bulb outdoor = 95°F).* Air-Conditioning and Refrigeration Institute standards for the design,fabrication, and installation of heating, ventilating, and airconditioning equipment.IV.237 (Revised 5/81)