Revision history [back]

I am trying to implement PAU+FCU with chilled water loop.
Since maximum flow rate specified in Fan:VariableVolume is bigger than minimum flow rate autosized by Controller:OutdoorAir, I expected that maximum flow rate specified in Fan:VariableVolume will be used for maximum flow rate in Controller:OutdoorAir. However, checking the result, maximum flow rate is same as minimum flow rate as shown below.

Then I start to wonder how maximum flow rate for economizer is calculated.
Can anyone tell me how maximum outdoor air flow rate is calculated in Controller:OutdoorAir?

I am trying to implement PAU+FCU with chilled water loop.
Since maximum flow rate specified in Fan:VariableVolume is bigger than minimum flow rate autosized by Controller:OutdoorAir, I expected that maximum flow rate specified in Fan:VariableVolume will be used for maximum flow rate in Controller:OutdoorAir. However, checking the result, maximum flow rate is same as minimum flow rate as shown below.

Then I start to wonder how maximum flow rate for economizer is calculated.
Can anyone tell me how maximum outdoor air flow rate is calculated in Controller:OutdoorAir?

I am trying to implement PAU+FCU with chilled water loop.
Since maximum flow rate specified in Fan:VariableVolume is bigger than minimum flow rate autosized by Controller:OutdoorAir, I expected that maximum flow rate specified in Fan:VariableVolume will be used for maximum flow rate in Controller:OutdoorAir. However, checking the result, maximum flow rate is same as minimum flow rate as shown below.

Then I start to wonder how maximum flow rate for economizer is calculated.
Can anyone tell me how maximum outdoor air flow rate is calculated in Controller:OutdoorAir?

I am trying to implement PAU+FCU with chilled water loop.
Since maximum flow rate specified in Fan:VariableVolume is bigger than minimum flow rate autosized by Controller:OutdoorAir, I expected that maximum flow rate specified in Fan:VariableVolume will be used for maximum flow rate in Controller:OutdoorAir. However, checking the result, maximum flow rate is same as minimum flow rate as shown below.

Then I start to wonder how maximum flow rate for economizer is calculated.
Can anyone tell me how maximum outdoor air flow rate is calculated in Controller:OutdoorAir?

Controller:OutdoorAir,
    A_LZ_Office_sys OA Controller,  !- Name
    A_LZ_Office_sys Relief Air Outlet,  !- Relief Air Outlet Node Name
    A_LZ_Office_sys Air Loop Inlet,  !- Return Air Node Name
    A_LZ_Office_sys Mixed Air Outlet,  !- Mixed Air Node Name
    A_LZ_Office_sys Outdoor Air Inlet,  !- Actuator Node Name
    autosize,                !- Minimum Outdoor Air Flow Rate {m3/s}
    autosize,                !- Maximum Outdoor Air Flow Rate {m3/s}
    DifferentialEnthalpy,    !- Economizer Control Type
    ModulateFlow,            !- Economizer Control Action Type
    ,                        !- Economizer Maximum Limit Dry-Bulb Temperature {C}
    ,                        !- Economizer Maximum Limit Enthalpy {J/kg}
    ,                        !- Economizer Maximum Limit Dewpoint Temperature {C}
    ,                        !- Electronic Enthalpy Limit Curve Name
    ,                        !- Economizer Minimum Limit Dry-Bulb Temperature {C}
    NoLockout,               !- Lockout Type
    ProportionalMinimum;     !- Minimum Limit Type

Fan:VariableVolume,
    A_LZ_Office_sys Supply Fan,  !- Name
    Office HVAC On (BEAM),   !- Availability Schedule Name
    0.8,                     !- Fan Total Efficiency
    1600,                    !- Pressure Rise {Pa}
    145.2,                   !- Maximum Flow Rate {m3/s}
    Fraction,                !- Fan Power Minimum Flow Rate Input Method
    0.0,                     !- Fan Power Minimum Flow Fraction
    ,                        !- Fan Power Minimum Air Flow Rate {m3/s}
    0.9,                     !- Motor Efficiency
    1,                       !- Motor In Airstream Fraction
    0.0015302446,            !- Fan Power Coefficient 1
    0.0052080574,            !- Fan Power Coefficient 2
    1.1086242,               !- Fan Power Coefficient 3
    -0.11635563,             !- Fan Power Coefficient 4
    0,                       !- Fan Power Coefficient 5
    A_LZ_Office_sys Heating Coil Outlet,  !- Air Inlet Node Name
    A_LZ_Office_sys Supply Fan Outlet;  !- Air Outlet Node Name