When setting the cooling schedule, it is found that the seasonal schedule does not work, while the heating schedule works,



No change in summer temperature

cece.gh (165.9 KB)

Hey @123songhaodong ,

I agree that this is odd. From your sample file you are setting up the seasonal schedule correctly. I checked the OSM file that gets output in the OpenStudio application and I can see that the schedule gets translated correctly there. And it appears to be translated correctly to IDF. It’s just that EnergyPlus seems to be ignoring the summer period of the schedule in the operation of the ideal air system.

So I’m a little inclined to think this is a bug in EnergyPlus, which should probably be reported on the unmethours forum.

In the meantime, I think you can get around this bug by using a Fixed Interval schedule in honeybee instead of the seasonal schedule.

Thank you so much, Chris. I will go to unmethours to reflect this issue.

Actually, I have an update and I figured out what is going on. There’s no bug in EnergyPlus or OpenStudio.

It’s just that the summer design day schedule of the Seasonal Schedule is set using the _base_schedule. And, in your case, the base schedule is a 50C cooling setpoint:

So your cooling system is effectively sized to zero since there’s no cooling demand when the thermostat setpoint is at 50C.

An easy way to address this is just by flipping the _base_schedule and the _season_scheds like so:


cece_CWM.gh (153.1 KB)

But, given that I can see how this case confused me, I think I will also add optional inputs for _summer_des_ and _winter_des_ schedules to the “HB Seasonal Schedule” component. This way, you’ll always be able to override whatever design day schedules are set from the _base_schedule. I’ll post back here once it is implemented.

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Ok, I updated the Seasonal Schedule component to have inputs for Summer and Winter design days:

Now, you can set up your schedule as you did originally but just specify that you want the cooling system to be sized with an assumption of a cooling setpoint of 26:


seasonal_sch_des_days.gh (147.4 KB)

You can get the new component with the LB Versioner within an hour or so.

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