SHW Templates and District SHW Creation

Hi Everyone,

This may or not be asked and answered based on @Elliot_Glassman 's post from last year (Default SHW Loop), but after reading that post, I decided to open my .OSM file and see what the output was. It looks like I have a district SHW and also one of the SHW’s from the templates available in Honeybee. I used the electric water heater template. The question is, do I need both systems? Is there a resource/tutorial video on how to set this up in Honeybee? I’m just modeling a hot water tank in a house…or at least trying to do that.

I assigned the Hot Water system with the Rhino Pollination interface to be in the Kitchen, Bathroom, and Basement. This system shows hot water to all the rooms in the model. Below is a screenshot, though I’m not sure how useful it is. Perhaps I’m missing the mark completely.

Thanks for your help!

Seems like the answer is no based on @chris 's reply in the linked thread and from here:

So does that mean that a Hot Water System is applied to all rooms and you have to go into Open Studio and make the values zero for the equipment? I guess that’s the part I’m not understanding. Shouldn’t my hot water only be applied to the rooms selected in pollination? Or does the program type “Midrise Apt” assign a district heating system?

Hi @bwatanabe ,

It sense there are a few levels of confusion here but, trying to pick this apart, it sounds like you only assigned the SHW system to three of the your many rooms that have service hot water usage. So the 3 rooms that you assigned the electric hot water system to are having their hot water supplied through that system while all of your other rooms with hot water usage are getting served by the default district hot water system.

It sounds like you want all of your rooms to be served by the same hot water system so you should assign the SHW System to all of them in the PO_EditRoomRpoperties window or pass all of them through the SHW System component (if you’re in Grasshopper).

Alternatively, if those other rooms aren’t supposed to have any hot water usage, you could set the hot water usage of those rooms to zero. You can do this either with the PO_EditRoomProperties command and editing the loads or by using the HB Apply Load Values component.

Hey @chris ,

Yes, multiple levels of confusion. I’m not quite as sophisticated as a lot of the folks that post in the forums, so I apologize for the rudimentary questions.

I did what you suggested in the last part of your reply. I hadn’t even thought to look at the loads tab in Pollination. In general is there a reason that folks choose to utilize the program to specify a hot water system? In a house it’s easy to just click on the rooms and zero out the load, but if it were a high rise residential building with multiple fixtures per unit, how do folks deal with that?

Here’s how I zero’d out the load, by the way. Does this look like how you ought to do it?


Also, when you’re energy modeling, doesn’t the location of the hot water heater matter? I don’t see where you actually assign that. There’s an insane amount of inputs in OpenStudio, but the location doesn’t appear to be one of them.