Unmet Hours - RSS feedhttps://unmethours.com/questions/Question-and-Answer Resource for the Building Energy Modeling CommunityenSat, 07 Aug 2021 09:48:33 -0500resstock ashp capacity coefficients are all the same?https://unmethours.com/question/58435/resstock-ashp-capacity-coefficients-are-all-the-same/ I am using resstock to generate building .idfs using air source heat pumps, but the idf's seem to all have the same capacity biquadratic curve coefficients. I've traced it down to resstock's source code, where it seems like they [hard-code](https://github.com/NREL/resstock/blob/bf0bbb7a282ef1326b6d924d664db9db0c12dff7/resources/measures/HPXMLtoOpenStudio/resources/hvac.rb#L452) in capacity and EIR coefficients for all single stage heat pumps, regardless of efficiency or SEER.
Is there any way to get Resstock to generate capacity coefficients that match the sampled ASHP efficiency? Follow-up question, where can I find sample coefficients based on SEER/HSPF/Capacity?
Fri, 06 Aug 2021 14:48:38 -0500https://unmethours.com/question/58435/resstock-ashp-capacity-coefficients-are-all-the-same/Answer by shorowit for <p>I am using resstock to generate building .idfs using air source heat pumps, but the idf's seem to all have the same capacity biquadratic curve coefficients. I've traced it down to resstock's source code, where it seems like they <a href="https://github.com/NREL/resstock/blob/bf0bbb7a282ef1326b6d924d664db9db0c12dff7/resources/measures/HPXMLtoOpenStudio/resources/hvac.rb#L452">hard-code</a> in capacity and EIR coefficients for all single stage heat pumps, regardless of efficiency or SEER.</p>
<p>Is there any way to get Resstock to generate capacity coefficients that match the sampled ASHP efficiency? Follow-up question, where can I find sample coefficients based on SEER/HSPF/Capacity?</p>
https://unmethours.com/question/58435/resstock-ashp-capacity-coefficients-are-all-the-same/?answer=58485#post-id-58485Most EnergyPlus performance curves are normalized. So the capacity and efficiency (COP) values will change based on SEER/HSPF/capacity, but the curves remain the same. Sat, 07 Aug 2021 09:29:04 -0500https://unmethours.com/question/58435/resstock-ashp-capacity-coefficients-are-all-the-same/?answer=58485#post-id-58485Comment by zel3 for <p>Most EnergyPlus performance curves are normalized. So the capacity and efficiency (COP) values will change based on SEER/HSPF/capacity, but the curves remain the same. </p>
https://unmethours.com/question/58435/resstock-ashp-capacity-coefficients-are-all-the-same/?comment=58486#post-id-58486Ah I see, thanks. So these curves are multiplied by the "Gross Rated Heating Capacity/COP" that are determined by the autosizing algorithm and the sampled efficiency?Sat, 07 Aug 2021 09:48:33 -0500https://unmethours.com/question/58435/resstock-ashp-capacity-coefficients-are-all-the-same/?comment=58486#post-id-58486