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