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### ideas on a workaround to override default control measures for water flow in Air Loop HVAC coils

I am using the BCVTB to control E+ air loop simulations using building controllers. The simulated air handlers all have a heating and cooling coil delivering air via AirterminalSingleDuct:Uncontrolled, thus the supply air temperature from the fan outlet node has to be carefully controlled to produce nice simulation results. My physical controllers command the position of the heating and cooling valve, and I would very much like to use these outputs to set the desired portion of maximum mass flow rate to the coils when there is heating/cooling demand. For instance, ideally this would be accomplished through the use of SetpointManager:Scheduled in order to communicate the coil flow rate at any given time. In other words, I have attempted to replace the Controller:WaterCoil objects in the AirLoopHVAC:ControllerList with setpoint managers in lieu of default controllers. I have found that this will not work because the list is specifically looking for a Controller:WaterCoil. I have investigated possible workarounds via EMS and UserDefined objects, but so far have found no evidence of a reliable workaround here. I realize that the point of the Controller:WaterCoil is that E+ automatically sets the required flow based on management of the required AirLoop Supply Air Temperature. For this research, however, (due to the nature of the actual control logic), it would be desirable to control the water flow and report the SAT back to the controller. I could be wrong, but it seems EMS oriented control of water flow lends itself readily to plant control and not necessarily to control of water through Air Loop Coils. In summary, my first choice would be to control the coil water flow, as it represents the actual control situation for this system. I already know that I can control the coils indirectly by sending in the desired SAT, only the logic of these particular controllers will have to be tweaked if this is indeed the only option. Does anyone have any ideas on a workaround to override default control measures for water flow in Air Loop HVAC coils? airloophvac.jpg controllerlist.jpg error.jpg setpointmanager.jpg visualOS.jpg visualOS2.jpg

### ideas on a workaround to override default control measures for water flow in Air Loop HVAC coils

I am using the BCVTB to control E+ air loop simulations using building controllers. The simulated air handlers all have a water based heating and cooling coil delivering conditioned air via AirterminalSingleDuct:Uncontrolled, thus the supply air temperature from the fan outlet node has to be carefully controlled to produce nice simulation results. My physical controllers command the position of the heating and cooling valve, and I would very much like to use these outputs to set the desired portion of maximum mass flow rate to the coils when there is heating/cooling demand. For instance, ideally this would be accomplished through the use of SetpointManager:Scheduled in order to communicate the coil flow rate at any given time. In other words, I have attempted to replace the Controller:WaterCoil objects in the AirLoopHVAC:ControllerList with setpoint managers in lieu of default controllers. I have found that this will not work because the list is specifically looking for a Controller:WaterCoil. I have investigated possible workarounds via EMS and UserDefined objects, but so far have found no evidence of a reliable workaround here. I realize that the point of the Controller:WaterCoil is that E+ automatically sets the required flow based on management of the required AirLoop Supply Air Temperature. For this research, however, (due to the nature of the actual control logic), it would be desirable to control the water flow and report the SAT back to the controller. I could be wrong, but it seems EMS oriented control of water flow lends itself readily to plant control and not necessarily to control of water through Air Loop Coils. In summary, my first choice would be to control the coil water flow, as it represents the actual control situation for this system. I already know that I can control the coils indirectly by sending in the desired SAT, only the logic of these particular controllers will have to be tweaked if this is indeed the only option. Does anyone have any ideas on a workaround to override default control measures for water flow in Air Loop HVAC coils? airloophvac.jpg controllerlist.jpg error.jpg setpointmanager.jpg visualOS.jpg visualOS2.jpg

### ideas on a workaround to override default control measures for water flow in Air Loop HVAC coils

I am using the BCVTB to control E+ air loop simulations using building controllers. The simulated air handlers all have a water based heating and cooling coil coils delivering conditioned air via AirterminalSingleDuct:Uncontrolled, thus the supply air temperature from the fan outlet node has to be carefully controlled to produce nice simulation results. My physical controllers command the position of the heating and cooling valve, and I would very much like to use these outputs to set the desired portion of maximum mass flow rate to the coils when there is heating/cooling demand. For instance, ideally this would be accomplished through the use of SetpointManager:Scheduled in order to communicate the coil flow rate at any given time. In other words, I have attempted to replace the Controller:WaterCoil objects in the AirLoopHVAC:ControllerList with setpoint managers in lieu of default controllers. I have found that this will not work because the list is specifically looking for a Controller:WaterCoil. I have investigated possible workarounds via EMS and UserDefined objects, but so far have found no evidence of a reliable workaround here. I realize that the point of the Controller:WaterCoil is that E+ automatically sets the required flow based on management of the required AirLoop Supply Air Temperature. For this research, however, (due to the nature of the actual control logic), it would be desirable to control the water flow and report the SAT back to the controller. I could be wrong, but it seems EMS oriented control of water flow lends itself readily to plant control and not necessarily to control of water through Air Loop Coils. In summary, my first choice would be to control the coil water flow, as it represents the actual control situation for this system. I already know that I can control the coils indirectly by sending in the desired SAT, only the logic of these particular controllers will have to be tweaked if this is indeed the only option. Does anyone have any ideas on a workaround to override default control measures for water flow in Air Loop HVAC coils? airloophvac.jpg controllerlist.jpg error.jpg setpointmanager.jpg visualOS.jpg visualOS2.jpg

 4 retagged __AmirRoth__ 4388 ●5 ●16 http://bleedinggreenna...

### ideas on a workaround to override default control measures for water flow in Air Loop HVAC coils

I am using the BCVTB to control E+ air loop simulations using building controllers. The simulated air handlers all have water based heating and cooling coils delivering conditioned air via AirterminalSingleDuct:Uncontrolled, thus the supply air temperature from the fan outlet node has to be carefully controlled to produce nice simulation results. My physical controllers command the position of the heating and cooling valve, and I would very much like to use these outputs to set the desired portion of maximum mass flow rate to the coils when there is heating/cooling demand. For instance, ideally this would be accomplished through the use of SetpointManager:Scheduled in order to communicate the coil flow rate at any given time. In other words, I have attempted to replace the Controller:WaterCoil objects in the AirLoopHVAC:ControllerList with setpoint managers in lieu of default controllers. I have found that this will not work because the list is specifically looking for a Controller:WaterCoil. I have investigated possible workarounds via EMS and UserDefined objects, but so far have found no evidence of a reliable workaround here. I realize that the point of the Controller:WaterCoil is that E+ automatically sets the required flow based on management of the required AirLoop Supply Air Temperature. For this research, however, (due to the nature of the actual control logic), it would be desirable to control the water flow and report the SAT back to the controller. I could be wrong, but it seems EMS oriented control of water flow lends itself readily to plant control and not necessarily to control of water through Air Loop Coils. In summary, my first choice would be to control the coil water flow, as it represents the actual control situation for this system. I already know that I can control the coils indirectly by sending in the desired SAT, only the logic of these particular controllers will have to be tweaked if this is indeed the only option. Does anyone have any ideas on a workaround to override default control measures for water flow in Air Loop HVAC coils? airloophvac.jpg controllerlist.jpg error.jpg setpointmanager.jpg visualOS.jpg visualOS2.jpg

 5 No.5 Revision Julien Marrec 26528 ●37 ●69 http://www.effibem.com/

### ideas on a workaround to override default control measures for water flow in Air Loop HVAC coils

I am using the BCVTB to control E+ air loop simulations using building controllers. controllers.

The simulated air handlers all have water based heating and cooling coils delivering conditioned air via AirterminalSingleDuct:Uncontrolled, thus the supply air temperature from the fan outlet node has to be carefully controlled to produce nice simulation results. My physical controllers command the position of the heating and cooling valve, and I would very much like to use these outputs to set the desired portion of maximum mass flow rate to the coils when there is heating/cooling demand. For instance, ideally this would be accomplished through the use of SetpointManager:Scheduled in order to communicate the coil flow rate at any given time.

In other words, I have attempted to replace the Controller:WaterCoil objects in the AirLoopHVAC:ControllerList with setpoint managers in lieu of default controllers. I have found that this will not work because the list is specifically looking for a Controller:WaterCoil. I have investigated possible workarounds via EMS and  and UserDefined objects, but so far have found no evidence of a reliable workaround here. here.

I realize that the point of the Controller:WaterCoil is that E+ automatically sets the required flow based on management of the required AirLoop Supply Air Temperature. Temperature. For this research, however, (due to the nature of the actual control logic), it would be desirable to control the water flow and report the SAT back to the controller. I could be wrong, but it seems EMS oriented control of water flow lends itself readily to plant control and not necessarily to control of water through Air Loop Coils.

In summary, my first choice would be to control the coil water flow, as it represents the actual control situation for this system. I already know that I can control the coils indirectly by sending in the desired SAT, only the logic of these particular controllers will have to be tweaked if this is indeed the only option. option.

Does anyone have any ideas on a workaround to override default control measures for water flow in Air Loop HVAC coils? coils?

visualOS2.jpg