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OpenStudio error FindRootSimpleController

Hi All, I have a project with several 90.1-2007 App G Baseline System 8 - VAV systems with CHW cooling and electric heating. The model is meeting loads and the simulation completes successfully, but I get a severe error for each CHW coil controller that looks like this:


* Severe * FindRootSimpleController: Controller error for controller = "CONTROLLER WATER COIL 2"

* ~~~ * Environment=DENVER INTL AP ANN CLG .4% CONDNS DP=>MDB, at Simulation time=07/21 20:00 - 20:15

* ~~~ * Controller function is inconsistent with user specified controller action = Reverse action

* ~~~ * Actuator will be set to maximum action

* ~~~ * Controller control type=Temperature

* ~~~ * Controller temperature setpoint = 11.39 [C]

* ~~~ * Controller sensed temperature = 12.16 [C]

* ~~~ * Controller actuator mass flow rate set to 0.60 [kg/s]

* ~~~ * Controller actuator temperature = 12.22 [C]

* ~~~ * Note: Chilled water coils should be reverse action and the entering chilled

* ~~~ * water temperature (controller actuator temperature) should be below the setpoint temperature

* ~~~ * Note: Hot water coils should be normal action and the entering hot

* ~~~ * water temperature (controller actuator temperature) should be above the setpoint temperature


I have triple checked the model and the coil controllers have the correct action. I have heard that this error may show up because of something else going on with airloops, but I can't find anything amiss. The model seems ok otherwise, though I suspect that heating use might be a bit low (multifamily building), which might be triggering this issue: https://github.com/NREL/EnergyPlus/issues/4187

Should I be concerned? Any resolution? Thanks in advance!

OpenStudio error FindRootSimpleController

Hi All, I have a project with several 90.1-2007 App G Baseline System 8 - VAV systems with CHW cooling and electric heating. The model is meeting loads and the simulation completes successfully, but I get a severe error for each CHW coil controller that looks like this:


* Severe * FindRootSimpleController: Controller error for controller = "CONTROLLER WATER COIL 2"

* ~~~ * Environment=DENVER INTL AP ANN CLG .4% CONDNS DP=>MDB, at Simulation time=07/21 20:00 - 20:15

* ~~~ * Controller function is inconsistent with user specified controller action = Reverse action

* ~~~ * Actuator will be set to maximum action

* ~~~ * Controller control type=Temperature

* ~~~ * Controller temperature setpoint = 11.39 [C]

* ~~~ * Controller sensed temperature = 12.16 [C]

* ~~~ * Controller actuator mass flow rate set to 0.60 [kg/s]

* ~~~ * Controller actuator temperature = 12.22 [C]

* ~~~ * Note: Chilled water coils should be reverse action and the entering chilled

* ~~~ * water temperature (controller actuator temperature) should be below the setpoint temperature

* ~~~ * Note: Hot water coils should be normal action and the entering hot

* ~~~ * water temperature (controller actuator temperature) should be above the setpoint temperature


I have triple checked the model and the coil controllers have the correct action. I have heard that this error may show up because of something else going on with airloops, but I can't find anything amiss. The model seems ok otherwise, though I suspect that heating use might be a bit low (multifamily building), which might be triggering this issue: https://github.com/NREL/EnergyPlus/issues/4187

Should I be concerned? Any resolution? I am using OpenStudio v1.8.0. Thanks in advance!

OpenStudio error FindRootSimpleController

Hi All, I have a project with several 90.1-2007 App G Baseline System 8 - VAV systems with CHW cooling and electric heating. The model is meeting loads and the simulation completes successfully, but I get a severe error for each CHW coil controller that looks like this:


*

** Severe  * ** FindRootSimpleController: Controller error for controller = "CONTROLLER WATER COIL 2"

* ~~~ * 2" ** ~~~ ** Environment=DENVER INTL AP ANN CLG .4% CONDNS DP=>MDB, at Simulation time=07/21 20:00 - 20:15

* ~~~ * 20:15 ** ~~~ ** Controller function is inconsistent with user specified controller action = Reverse action

* ~~~ * action ** ~~~ ** Actuator will be set to maximum action

* ~~~ * action ** ~~~ ** Controller control type=Temperature

* ~~~ * type=Temperature ** ~~~ ** Controller temperature setpoint = 11.39 [C]

* ~~~ * [C] ** ~~~ ** Controller sensed temperature = 12.16 [C]

* ~~~ * [C] ** ~~~ ** Controller actuator mass flow rate set to 0.60 [kg/s]

* ~~~ * [kg/s] ** ~~~ ** Controller actuator temperature = 12.22 [C]

* ~~~ * [C] ** ~~~ ** Note: Chilled water coils should be reverse action and the entering chilled

* ~~~ * chilled ** ~~~ ** water temperature (controller actuator temperature) should be below the setpoint temperature

* ~~~ * temperature ** ~~~ ** Note: Hot water coils should be normal action and the entering hot

* ~~~ * hot ** ~~~ ** water temperature (controller actuator temperature) should be above the setpoint temperature


temperature

I have triple checked the model and the coil controllers have the correct action. I have heard that this error may show up because of something else going on with airloops, but I can't find anything amiss. The model seems ok otherwise, though I suspect that heating use might be a bit low (multifamily building), which might be triggering this issue: https://github.com/NREL/EnergyPlus/issues/4187

Should I be concerned? Any resolution? I am using OpenStudio v1.8.0. Thanks in advance!