Manual S was updated in late 2023 to allow for saner sizing of heat pumps in colder climates using N.2.3.4.2 "Variable-capacity equipment sizing condition: advanced" Will BEopt3's sizing algorithm be updated accordingly?
Yes, it's on our radar. We're hoping to incorporate it in OpenStudio-HPXML later this year, which would make it available in a subsequent BEopt release.
As Scott mentioned, it is planned. OS-HPXML would likely have an additional field for HeatPumpSizingMethodology (and potentially also HeatPumpBackupSizingMethodology), and the methods would be named to distinguish between the two.
HeatPumpSizingMethodology:ACCA vs. HeatPumpSizingMethodology:ACCA2023, or something like that.
See https://openstudio-hpxml.readthedocs.... for what OS-HPXML currently uses.
There are some challenges with implementing N.2.3.4 - Variable Capacity (either Advanced or Dry) because of the "minimum compressor cooling size factor" stipulations. I believe our current OS-HPXML implementation doesn't define this variable, as it is new to ACCA Manual S 2023. We will start by addressing the "Standard Sizing Condition" update for single and 2-speed equipment, which may be just updated oversize/undersize limits.
Asked: 2024-12-10 07:33:31 -0600
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Last updated: Dec 16
