Daily Heating Load Peaks at 6AM, 10AM, 5PM?

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Doing a comparison study of different heating methods at various locations and all of my results have average daily heating load peaks at 6AM, 10AM, and 5PM.

It should also be mentioned that my data are translated half an hour prior, as DView exports on every half hour. Therefore, in DView, these results would be at 630AM, 1030AM, and 530PM.

The attached image is averaged daily loads over an entire year. Is there documentation that I can reference as to why this is? Any suggestions as to why BEopt produces this result would be greatly appreciated!

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EDIT: Also attached is Table 15 from the Building America House Simulation Protocols, which displays ventilation events that have been suggested as the causes for these peaks. Unfortunately, these times do not correspond with the peaks that occur from averaging each hour of the DView's Mains Heating Load (as seen in the first image).

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CDinkle

asked 2021-04-03 22:35:00 -0500, updated 2021-04-05 11:44:15 -0500

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You are seeing increased heating during hours when the kitchen/bathroom exhaust fans or (vented) clothes dryer are running, which causes outdoor air to be introduced to the home. You can read about these assumptions in the Building America House Simulation Protocols linked from the BEopt help menu.

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shorowit

answered 2021-04-05 09:35:52 -0500

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Thank you for your response. Regarding your suggestion, the assumptions shown in the Building America House Simulation Protocols for when outdoor air is introduced into the home occur at times that do not correspond with the peaks shown in my averages, unfortunately. I've attached an image in the original post with the applicable Table.

Am I looking at the wrong table for what you've suggested? Thank you for the help!

CDinkle (2021-04-05 11:31:25 -0500) edit

Perhaps daylight savings time is coming into play?

shorowit (2021-04-05 11:47:07 -0500) edit

That is a great point, thank you.

CDinkle (2021-04-05 16:50:47 -0500) edit

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It could be the hours that the heating setpoint is changing from night setback to daytime setpoint and/or aligning with occupancy schedules.

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ericmartinpe

answered 2021-04-04 20:10:28 -0500

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Thank you for the prompt response. I do not have any setback options selected in my model; all heating setpoints are Option 10 in "Space Conditioning Schedules", which does not appear to have any setback hours for that option.

Where can I view the occupancy schedules in BEopt? Thanks again.

CDinkle (2021-04-04 20:43:08 -0500) edit