Clarification for HeatingSystem.heatpump_low_shutoff_temperature

[KarenWGard]

the HeatingSystem.heatpump_low_shutoff_temperature is used to determine whether the heat pump is allowed to operate at the same time as auxiliary heat. ASHRAE 90.1 RCT Rule 23-17 is currently using -56F as a cutoff temperature at or below which, heatpumps are considered to be operating continuously even when there is auxiliary heat. -56F is the lowest recorded temperature in a habitable area of the USA in the last 10-years (Cotton, Minnesota - January 27, 2019). There are arguments for using other temperatures:

-80F is the coldest recorded temperature in recent years in a habitable place... Yakustk, Russia - January 18, 2023
−459.67 F ... nothing colder.

The discussion about exactly what temperature the low number should be is purely academic, because no normal heat pump will have any capacity at these temperatures, but a number should be selected and communicated in the schema.

[JasonGlazer]

I am adding to the note:

For heat pumps with no lower temperature limit, this value should not be provided or set to -999.

This assumes that we have rules and RCT functionality that test for the presence of a data element value.

This will be included in 0.1.1

[claperle]

I am adding to the note:

For heat pumps with no lower temperature limit, this value should not be provided or set to -999.

This assumes that we have rules and RCT functionality that test for the presence of a data element value.

This will be included in 0.1.1

@JasonGlazer I like that more elegant solution!

[KarenWGard]

Yes. Very nice

…

On Thu, Dec 5, 2024, 13:31 claperle ***@***.***> wrote: I am adding to the note: For heat pumps with no lower temperature limit, this value should not be provided or set to -999. This assumes that we have rules and RCT functionality that test for the presence of a data element value. This will be included in 0.1.1 @JasonGlazer <https://github.com/JasonGlazer> I like that more elegant solution! — Reply to this email directly, view it on GitHub <#298 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/A3G3CLBUABXR4AMNHJ2CZVD2EBBQXAVCNFSM6AAAAABTBE4REWVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDKMRQGE4TCOBXGM> . You are receiving this because you authored the thread.Message ID: ***@***.*** com>