DOE-2 Reference Manual Version 2.1 - DOE2.com

18)19)20)21 )trying to change the system's responsiveness, or (3) attempting toreduce initial costs of construction by assuming a measure of risk(see keyword SIZING-RATIO in SYSTEM command).Heat Source Option: The user may choose between GAS-FURNACE,OIL-FURNACE, HOT-WATER, HOT-WATER/SOLAR, and ELECTRIC forHEAT-SOURCEs. The same code-words are available for the keywordsZONE-HEAT-SOURCE, PREHEAT-SOURCE, and BASEBOARD-SOURCE (exceptHOT-WATER/SOLAR should not be used with BASEBOARD-SOURCE).HEAT-PUMP is an appropriate option for the RESYS and PTAC systemsonly.Fan Placement Option: A choice between BLOW-THROUGH andDRAW-THROUGH type fan is provided.Motor Placement Option: The motors may be placed IN-AIRFLOW orOUTSIDE-AIRFLOW to correctly account for fan heat gain in the supplyair stream.0henable Windows: Windows may be opened for naturalT 1S option 1S available for the RESYS system only.NATURAL-VENT-AC, NATURAL-VENT-SCH, and VENT-TEMP-SCHsubcommand) .ventil ati on.(Seein SYSTEM-AIR22) Night Cycle Control: The user may specify the behavior of the fansdUrlng periods where the FAN-SCHEDULEs are not in operation.Although the fans may be turned off at night, to conserve energy,the night cycle control will turn the fans on to maintain thetemperature within the THROTTLING-RANGE, thus preventing buildingfreezeup.23) Fan Sizing Option: It is possible to select the size of theSUPPLY-CFM (supply air fan) to meet either the block, or building,peak load (COINCIDENT for SIZING-OPTION in the SYSTEM command) orthe sum of the individual zone peak loads (NON-COINCIDENT forSIZING-OPTION in the SYSTEM command).4. System Descriptionsa. Summation of LOADS to PLANT (SUM)This is actually not a secondary HVAC distribution system, but rather adiagnostic tool, which is used to 1) pass the hourly LOADS program output tothe PLANT program without simulating a system, 2) adjust the constant zonetemperatures specified in LOADS, 3) simulate the thermostat schedules (but notthe equipment), and 4) tabulate energy consumption by ZONE (or group ofZONEs). SUM is not a miscellaneous SYSTEM-TYPE for UNCONDITIONED zones.UNCONDITIONEO ZONEs should be assigned to another SYSTEM.Table IV.3 shows the commands and keywords that must be entered for thissimulation, as well as those that are applicable but optional (i .e., programuses default value if entry is omitted).I V.17 (Rev i sed 5/81)