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I have a chilled ceiling system. and I put the chilled water loop exit temperature as 13C and the design temperature difference as 5C. also in setpoint manager, the loop is controlled to supply 13C all the time. but when I ran the chilled ceiling system, the result shows the supply temperature increased to 20C and the return is much higher than design temperature too. the chiller CHW outlet and inlet node temperatures are pretty similar, the supply water is not 13C. What's the reason of the unexpected and fluctuated supply and return temperature?

In the surface node temperature output, there are many node temperature for one construction (14 nodes temperatures for a 4 layers roof construction), how can I know which node number represent which construction layer surface? Is there any rule of the node numbering?

Hi everyone,

I have a very basic question about setpoint schedule in EnergyPlus (I'm using DesignBuilder). when defining setpoint, we have a schedule to determine the setpoint/setback/no requirement of indoor air temperature, but at the same time, when we define the system operation,

1. What is the 'Availability Schedule' in 'Plant Loop Data'? when it's 'on' 24 hours, does it mean even no cooling requirement at night, the chilled water loop is still on?
2. Also under the 'PlantEquipmentOperation', there is also another 'Operation schedule' for the Scheme to define when the scheme is on and off.

My control is that in the day time, the system is on when the space is occupied; The system is off for 6 hours at night for passive discharge without system running, the left hours at night before occupancy in the morning, the system is on again to actively discharge the heat if necessary. but at this period, the space setpoint is not required (no setback neither) when system is on. How to define the control schedule?

Thank you very much for any help!

How can I get hourly temperature output for one layer of material in construction ? Material temperature is preferred since we are modeling phase change material performance, it's better to know the temperature change. In addition, how to add an extra report IDF file in DesignBuilder simulation?

is it possible to model a control logic as follows in either OpenStudio or DesignBuilder (I assume it's the same logic since using E+):

• if outdoor air temp is below 10C, the chiller is shut down;
• if outdoor air temp is above 10C, the chiller is used to provide 13C chilled water

in DesignBuilder, the "setpoint manager" has only 2 types - "scheduled" or "outdoor air reset" in the water loop. when using "outdoor air reset", only setpoint at outdoor low temp and high temp can be defined. How to achieve the control logic above?

Thank you very much. I saw the Fluid Cooler in the feature of DB too, but I couldn't find this component in the software.

thank you for the reply. it's greatly helpful. I tried to find FluidCooler in the latest version DesignBuilder but I still couldn't find anything relevant neither from the software nor from the tutorial manual.

Hi all,

I'm a beginner of OpenStudio. I have been working on a phase change material (PCM) modelling project and I try to model it in DesignBuilder. Now the problem is the system has a dry cooler as the prior equipment to supply chilled water to the chilled ceiling (PCM), but I couldn't find the dry cooler component in DesignBuilder.

1. is it possible to model dry cooler in DesignBuilder by using another system instead? basically it's a heat exchanger of outdoor air and water (no refrigeration cycle);
2. is Openstudio capable of modelling Phase Change Material and is dry cooler available in the system?

Thank you for any idea and suggestion!