DOE-2 Reference Manual Version 2.1 - DOE2.com

8. SYSTEM-FANSThe function of the SYSTEM-FANS instruction is to provide information onsupply and retul"n fan operating schedules, control modes, static pressures, andefficiencies. In short, this instruction provides everything the program needsto know (with the exception of fan capacity and flow rate) for calculation ofthe energy consumed by and the heat input from these fans. The same type ofinformation is provided for exhaust fans, if any, at the zone level (keywordsEXHAUST-CFM, EXHAUST-STATIC, etc. in ZONE-AIR instruction). SeveralSYSTEM-FANS instructions may be entered if the facility is served by more thanone system and/or it is desired to conduct parametric runs.SYSTEM-FANS is a "subcommand" of SYSTEM and, as such, can be used to inputa subset of data to SYSTEM.An alternative mode for data entry is to complete and enter SYSTEM-FANSkeywords and their values directly into the SYSTEM command (if this approach ischosen, omit the SYSTEM-FANS keyword in SYSTEM).SYSTEM-FANSFAN-SCHEDULEFAN-CONTROLinforms the SDL Processor that the data to follow arerelated to the operation of system supply and return fans.A unique user-defined name must be entered in the U-namefield of each SYSTEM-FANS instruction. Omission of thisentry in the" subcommand" wi 11 cause an error.is the U-name of the SCHEDULE instruction that specifies thetime periods (hours and days) during which this system'sfans (supply, return, and exhaust) are operating and notoperating (see Chap. II for information on SCHEDULEinstruction). If the hourly values in the SCHEDULE that isreferenced by FAN-SCHEDULE are positive, such as 1, the fansare "on". If the hourly SCHEDULE values are 0, the fans are"off" but may be turned on by NIGHT-CYCLE-CTRL, if ZONEtemperatures warrant it. If the hourly SCHEDULE values arenegative, such as -1, the fans are not permitted to be "on"for any reason. If the user does not specify a U-name forthis keyword and an associated SCHEDULE, the program willassume the fans run continuously.If the fans (for all SYSTEM-TYPEs except FPH) are scheduledto be "off" (hourly SCHEDULE values equal 0), only baseboardunits (if specified) can be operational. Thus for strictlyforced air systems, heating is available only during thetime periods when the fans are scheduled to be "on", unlessthere are baseboard heating elements. One exception to thisrule is to specify CYCLE-aN-ANY or CYCLE-aN-FIRST forNIGHT-CYCLE-CTRL.Input for this keyword is the code-word that identifies thekind of flow reduction or control methods to be simulated.See Table IV.35 for the code-words and a brief descriptionof the method each represents. The program calculates theIV.221 (Revised 5/81)