Error in EnergyPlus

hwgarycheung · Posts: 1

I developed a model using Designbuilder and exported to EnergyPlus. During simulation, I found several errors . My colleague and I have already tired our very best to solve the problems but still failed. There are 13 zones (7 supported by a single duct CAV system and 6 by FCU system) for the buildings and 2 errors were found. The first one stated that the branch flow rate was out of bound. How can I make it bound? I don't know how to adjust/control the water flow rate after the pump outlet. People said the "Constant Primary Variable Secondary" option has bug. Is it true? What can I do now?
The second problem is about the controller. The error message showed that the chilled water temperature is too high to cool the air. Can you tell me what went wrong to make the water temperature so high? Simulation usually terminated after 1 to 3 months run. Does anyone has ideas about what went wrong?

1st error
All the branches fed by the chiller group issued this warning:

** Warning ** PlantFlowResolver: Branch flow rates out of bounds, for Plant Loop=CHILLED WATER PLANT CHILLED WATER LOOP, Branch=CAV 6 COOLING COIL CHW BRANCH
** ~~~ ** Conditions should be: 740.282 <= 56.945 MWB, 07/21 00:00 - 00:10
** Warning ** PlantFlowResolver: Branch flow rates out of bounds, for Plant Loop=CHILLED WATER PLANT CHILLED WATER LOOP, Branch=CAV 7 COOLING COIL CHW BRANCH
** ~~~ ** Conditions should be: 740.282 <= 56.945 MWB, 07/21 00:00 - 00:01
** ~~~ ** Controller function is inconsistent with user specified controller action = Reverse action
** ~~~ ** Actuator will be set to maximum action
** ~~~ ** Controller control type=Temperature
** ~~~ ** Controller temperature set point = 14.42 [C]
** ~~~ ** Controller sensed temperature = 45.45 [C]
** ~~~ ** Controller actuator mass flow rate set to 93.65 [kg/s]
** ~~~ ** Controller actuator temperature = 52.07 [C]

Laurent_Support · Posts: 292 Location: Vincennes

Hello,

It is difficult to answer this king of problem without the model.
Could you tel me what DesignBuilder version you're using, what E+ version you selected and if possible could you post your model so we can run test ?

Thank you.

Login