DOE-2 Reference Manual Version 2.1 - DOE2.com

this system can operate from one thermostat set point, which is specified viaHEAT-TEMP-SCH. To obtain the same physical results for the DDS system, theuser may alternatively employ a mixing box with a constant volume output.Procedure:(1) Specify SYSTEM-TYPE = MZS, DDS, or PMZS in the SYSTEM command.(2) Specify MIN-CFM-RATIO (in either the ZONE command or in the SYSTEM­TERMINAL subcommand) as equal to 1.0, or allow it to default to thatvalue. This assures a constant volume mixed air flow entering allZONEs in this SYSTEM.(3) Specify COOL-CONTROL in the SYSTEM-CONTROL subcommand equal toCONSTANT, RESET, or SCHEDULED. This establishes the method forsetting the temperature of the cooling supply air that will be sentto all ZONEs in the SYSTEM. If the user does not specify a valuefor COOL-CONTROL, it will default to CONSTANT and COOL-SET-T willdefault to MIN-SUPPLY-T (a constant cold deck temperature the yeararound) .(4) Specify HEAT-CONTROL in the SYSTEM-CONTROL subcommand equal toCONSTANT, RESET, or SCHEDULED. This establishes the method forsetting the temperature of the heating supply air that will be sentto all ZONEs in the SYSTEM. If the user does not specify a valuefor HEAT-CONTROL, it will default to CONSTANT and HEAT-SET-T willdefault to MAX-SUPPLY-T (a constant hot deck temperature the yeararound) .(5) Specify HEAT-TEMP-SCH in the ZONE-CONTROL subcommand and an associatedSCHEDULE with hourly values of ZONE thermostat set pointtemperature.Specify a HEAT-TEMP-SCH for each conditioned ZONE in the SYSTEM.These set point temperatures will be used to modulate the air flowin the cold and hot air ducts to the ZONE. If the user does notspecify a HEAT-TEMP-SCH for a ZONE, it will be cooled but not heated(except for baseboard heaters when BASEBOARD-CTRL = OUTDOOR-RESET).If the user desires to have a temperature "setup" in the summer, thisshould be reflected in the SCHEDULE specified for HEAT-TEMP-SCH andthe HEATING-SCHEDULE during the setup period should be set to off.This will prevent the heating system from wasting energy in thesummer, in an attempt to hold the ZONE temperature up to the setuptemperature.(6) Specify THERMOSTAT-TYPE = PROPORTIONAL (or allow it to default) inthe ZONE-CONTROL subcommand.(7) The desired control strategy for the system has now been specified.To complete the input, specify values for the other keywords thatare appropriate to the SYSTEM-TYPE being simulated, or allow thesekeywords to default. This example is the first strategy in TableI V • 26.IV.120 (Revised 5/81)