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Hi all,

I am trying to simulate using AirflowNetwork and AirLoopHVAC with heat recovery in a multi-zone house. In a sample file (AirflowNetwork_MultiZone_SmallOffice_HeatRecoveryHXSL.idf) "Design Supply Air Flow Rate" is 1.9 (m3/s), but I would like to simulate with a lower flow rate. I changed the "Design Supply Air Flow Rate" and flow rate of fan in the sample to 0.05 (m3/s) and got the following error.

* Severe * AirflowNetwork: The airflow direction is opposite to the intended direction (from node 1 to node 2) in AirflowNetwork:Distribution:Linkage = ZONE1SUPPLY1LINK
* ~~~ * During Warmup, Environment=CHICAGO_IL_USA ANNUAL COOLING 1% DESIGN CONDITIONS DB/MCWB, at Simulation time=07/21 00:00 - 00:10
* ~~~ * The sum of the airflows entering the zone is greater than the airflows leaving the zone (e.g., wind and stack effect).
* ~~~ * Please check wind speed or reduce values of "Window/Door Opening Factor, or Crack Factor" defined in AirflowNetwork:MultiZone:Surface objects.

The error message says to reduce the Crack factor, but I don't want to reduce it because I want the simulation to account for the effect of cracks. If there is any other way to resolve this error, please let me know.

Thanks.

Hi all,

I am trying to simulate using AirflowNetwork and AirLoopHVAC with heat recovery in a multi-zone house. In a sample file (AirflowNetwork_MultiZone_SmallOffice_HeatRecoveryHXSL.idf) "Design Supply Air Flow Rate" is 1.9 (m3/s), but I would like to simulate with a lower flow rate. I changed the "Design Supply Air Flow Rate" and flow rate of fan in the sample to 0.05 (m3/s) and got the following error.

* Severe * AirflowNetwork: The airflow direction is opposite to the intended direction (from node 1 to node 2) in AirflowNetwork:Distribution:Linkage = ZONE1SUPPLY1LINK
* ~~~ * During Warmup, Environment=CHICAGO_IL_USA ANNUAL COOLING 1% DESIGN CONDITIONS DB/MCWB, at Simulation time=07/21 00:00 - 00:10
* ~~~ * The sum of the airflows entering the zone is greater than the airflows leaving the zone (e.g., wind and stack effect).
* ~~~ * Please check wind speed or reduce values of "Window/Door Opening Factor, or Crack Factor" defined in AirflowNetwork:MultiZone:Surface objects.

The error message says to reduce the Crack factor, but I don't want to reduce it because I want the simulation to account for the effect of cracks. If there is any other way to resolve this error, please let me know.

Thanks.

Hi all,

I am trying to simulate using AirflowNetwork and AirLoopHVAC with heat recovery in a multi-zone house. In a sample file (AirflowNetwork_MultiZone_SmallOffice_HeatRecoveryHXSL.idf) "Design Supply Air Flow Rate" is 1.9 (m3/s), but I would like to simulate with a lower flow rate. I changed the "Design Supply Air Flow Rate" and flow rate of fan in the sample to 0.05 (m3/s) and got the following error.

* Severe * AirflowNetwork: The airflow direction is opposite to the intended direction (from node 1 to node 2) in AirflowNetwork:Distribution:Linkage = ZONE1SUPPLY1LINK
* ~~~ * During Warmup, Environment=CHICAGO_IL_USA ANNUAL COOLING 1% DESIGN CONDITIONS DB/MCWB, at Simulation time=07/21 00:00 - 00:10
* ~~~ * The sum of the airflows entering the zone is greater than the airflows leaving the zone (e.g., wind and stack effect).
* ~~~ * Please check wind speed or reduce values of "Window/Door Opening Factor, or Crack Factor" defined in AirflowNetwork:MultiZone:Surface objects.

The error message says to reduce the Crack factor, but I don't want to reduce it because I want the simulation to account for the effect of cracks. If there is any other way to resolve this error, please let me know.

Thanks.

Hi all,

I am trying to simulate using AirflowNetwork and AirLoopHVAC with heat recovery in a multi-zone house. In a sample file (AirflowNetwork_MultiZone_SmallOffice_HeatRecoveryHXSL.idf) "Design Supply Air Flow Rate" is 1.9 (m3/s), but I would like to simulate with a lower flow rate. rate.

I changed the "Design Supply Air Flow Rate" and flow rate of fan in the sample to 0.05 (m3/s) and got the following error.

** Severe  * ** AirflowNetwork: The airflow direction is opposite to the intended direction (from node 1 to node 2) in AirflowNetwork:Distribution:Linkage = ZONE1SUPPLY1LINK 
 * <br>
**   ~~~   * **  During Warmup, Environment=CHICAGO_IL_USA ANNUAL COOLING 1% DESIGN CONDITIONS DB/MCWB, at Simulation time=07/21 00:00 - 00:10 
 * <br>
**   ~~~   * ** The sum of the airflows entering the zone is greater than the airflows leaving the zone (e.g., wind and stack effect). 
 * <br>
**   ~~~   * ** Please check wind speed or reduce values of "Window/Door Opening Factor, or Crack Factor" defined in AirflowNetwork:MultiZone:Surface objects.
objects.

Hi all,

I am trying to simulate using AirflowNetwork and AirLoopHVAC with heat recovery in a multi-zone house. In a sample file (AirflowNetwork_MultiZone_SmallOffice_HeatRecoveryHXSL.idf) "Design Supply Air Flow Rate" is 1.9 (m3/s), but I would like to simulate with a lower flow rate.

I changed the "Design Supply Air Flow Rate" and flow rate of fan in the sample to 0.05 (m3/s) and got the following error.

** Severe  ** AirflowNetwork: The airflow direction is opposite to the intended direction (from node 1 to node 2) in AirflowNetwork:Distribution:Linkage = ZONE1SUPPLY1LINK <br>
ZONE1SUPPLY1LINK
**   ~~~   **  During Warmup, Environment=CHICAGO_IL_USA ANNUAL COOLING 1% DESIGN CONDITIONS DB/MCWB, at Simulation time=07/21 00:00 - 00:10 <br>
00:10
**   ~~~   ** The sum of the airflows entering the zone is greater than the airflows leaving the zone (e.g., wind and stack effect). <br>
effect).
**   ~~~   ** Please check wind speed or reduce values of "Window/Door Opening Factor, or Crack Factor" defined in AirflowNetwork:MultiZone:Surface objects.

The error message says to reduce the Crack factor, but I don't want to reduce it because I want the simulation to account for the effect of cracks. If there is any other way to resolve this error, please let me know.

Thanks.

Hi all,

I am trying to simulate using AirflowNetwork and AirLoopHVAC with heat recovery in a multi-zone house. In a sample file (AirflowNetwork_MultiZone_SmallOffice_HeatRecoveryHXSL.idf) "Design Supply Air Flow Rate" is 1.9 (m3/s), but I would like to simulate with a lower flow rate.

I changed the "Design Supply Air Flow Rate" and flow rate of fan in the sample to 0.05 (m3/s) and got the following error.

** Severe  ** AirflowNetwork: The airflow direction is opposite to the intended direction (from node 1 to node 2) in AirflowNetwork:Distribution:Linkage = ZONE1SUPPLY1LINK
**   ~~~   **  During Warmup, Environment=CHICAGO_IL_USA ANNUAL COOLING 1% DESIGN CONDITIONS DB/MCWB, at Simulation time=07/21 00:00 - 00:10
**   ~~~   ** The sum of the airflows entering the zone is greater than the airflows leaving the zone (e.g., wind and stack effect).
**   ~~~   ** Please check wind speed or reduce values of "Window/Door Opening Factor, or Crack Factor" defined in AirflowNetwork:MultiZone:Surface objects.

The error message says to reduce the Crack factor, but I don't want to reduce it because I want the simulation to account for the effect of cracks. If there is any other way to resolve this error, please let me know.

Thanks.