RE: [EnergyPlus_Support] Controller:OutdoorAir minimums

Controller:OutdoorAir,
OA Controller 1, !- Name
Relief Air Outlet Node, !- Relief Air Outlet Node Name
Outdoor Air Mixer Inlet Node, !- Return Air Node Name
Mixed Air Node, !- Mixed Air Node Name
Outdoor Air Inlet Node, !- Actuator Node Name
0.25, !- Minimum Outdoor Air Flow Rate {m3/s}
1.6, !- Maximum Outdoor Air Flow Rate {m3/s}

ElectronicEnthalpy, !- Economizer Control Type
ModulateFlow, !- Economizer Control Action Type
23., !- Economizer Maximum Limit Dry-Bulb Temperature {C}
, !- Economizer Maximum Limit Enthalpy {J/kg}
13.5, !- Economizer Maximum Limit Dewpoint Temperature {C}
ElectronicEnthalpyCurveA,!- Electronic Enthalpy Limit Curve Name
14., !- Economizer Minimum Limit Dry-Bulb Temperature {C}
NoLockout, !- Lockout Type

FixedMinimum, !- Minimum Limit Type
OAFractionSched, !- Minimum Outdoor Air Schedule Name
,       !- Minimum Fraction of Outdoor Air Schedule Name
,       !- Maximum Fraction of Outdoor Air Schedule Name
,       !- Mechanical Ventilation Controller Name

TimeOfDayEconomizerSch, !- Time of Day Economizer Control Schedule Name
Yes, !- High Humidity Control
EAST ZONE, !- Humidistat Control Zone Name
0.9, !- High Humidity Outdoor Air Flow Ratio
Yes; !- Control High Indoor Humidity Based on Outdoor Humidity Ratio

Minimum fractin of outdoor air schedule name is to be used with the proportionalMinimum type. The minimum value can be above or below 0.25 (m3/s), dependent on the zone OA flow demand, including variation of people, etc. in conjunction with the Mechanical Ventilation Controller which controls both the minimum and maximum flow rate.

Dear Forum,

I'm trying to make sense of the I/O Reference description for two of the fields that affect the minimum OA. (shown below)

Can someone explain how these are different from each other?

Field: Minimum Outdoor Air Schedule Name
The name of a schedule whose values are decimal fractions (0.0 ? 1.0) that multiply the minimum outdoor air fraction. This schedule is useful for reducing the outdoor air flow rate to zero during unoccupied or start up hours. If this field is not input, the minimum outdoor air flow rate remains constant during the simulation period.

Field: Minimum Fraction of Outdoor Air Schedule Name
This is an optional field with the schedule values in decimal fractions (0.0-1.0). This field enables the user to limit the minimum amount of outdoor air permissible and thus also helps in getting at least the minimum amount of air in.

Look 'em in the eye: FREE Messenger video chat Chat Now!

__._,_.___

Primary EnergyPlus support is found at: http://energyplus.helpserve.com or send a message to energyplus-support@xxxxxxxx The primary EnergyPlus web site is found at: http://www.energyplus.gov The group web site is: http://groups.yahoo.com/group/EnergyPlus_Support/ Attachments are currently allowed but be mindful that not everyone has a high speed connection. Limit attachments to small files. EnergyPlus Documentation is searchable. Open EPlusMainMenu.pdf under the Documentation link and press the "search" button.

Your email settings: Individual Email|Traditional
Change settings via the Web (Yahoo! ID required)
Change settings via email: Switch delivery to Daily Digest | Switch to Fully Featured
Visit Your Group | Yahoo! Groups Terms of Use | Unsubscribe

__,_._,___