Question-and-Answer Resource for the Building Energy Modeling Community
Get started with the Help page
Ask Your Question

Revision history [back]

IECC standard reference HVAC system for VRF/DOAS

Hi energy modelers,

I'm building an IECC (2018) standard reference building energy model for a hotel with an air-cooled heat recovery VRF/DOAS system. The HVAC system which I should seemingly use for the baseline model does not make sense to me, so I wanted to get some input.

According to the attached snippet of the "Commercial Buildings - Total Building Performance" section, the standard reference building should be modeled with System 3: VAV/electric resistance heat. However, this doesn't make sense for a hotel, involves a complete remodel of the HVAC, and even requires me to re-model the secondary system (DOAS units), which IECC standard reference buildings don't usually do.

I know there is often leniency in interpretation, so if anyone has experience with this, please share. The ASHRAE 90.1 2016 standard reference HVAC system for a hotel in this climate zone is PTACs, which makes a lot more sense and would use the same DOAS units for the standard reference model. Additionally, if one could interpret the VRF system as "single-zone," then the IECC would require PTHPs as the standard reference HVAC system, which would also make sense.

Thanks in advance to anyone who can help!

Best, David

C:\fakepath\iecc snippet.png

IECC standard reference HVAC system for VRF/DOAS

Hi energy modelers,

I'm building an IECC (2018) standard reference building energy model for a hotel with an air-cooled heat recovery VRF/DOAS system. The HVAC system which I should seemingly use for the baseline model does not make sense to me, so I wanted to get some input.

According to the attached snippet of the "Commercial Buildings - Total Building Performance" section, the standard reference building should be modeled with System 3: VAV/electric resistance heat. However, this doesn't make sense for a hotel, involves a complete remodel of the HVAC, and even requires me to re-model the secondary system (DOAS units), which IECC standard reference buildings don't usually do.

I know there is often leniency in interpretation, so if anyone has experience with this, please share. The ASHRAE 90.1 2016 standard reference HVAC system for a hotel in this climate zone is PTACs, which makes a lot more sense and would use the same DOAS units for the standard reference model. Additionally, if one could interpret the VRF system as "single-zone," then the IECC would require PTHPs as the standard reference HVAC system, which would also make sense.

Thanks in advance to anyone who can help!

Best, David

C:\fakepath\iecc snippet.png

IECC standard reference HVAC system for VRF/DOAS

Hi energy modelers,

I'm building an IECC (2018) standard reference building energy model for a hotel with an air-cooled heat recovery VRF/DOAS system. The HVAC system which I should seemingly use for the baseline model does not make sense to me, so I wanted to get some input.

According to the attached snippet of the "Commercial Buildings - Total Building Performance" section, the standard reference building should be modeled with System 3: VAV/electric resistance heat. However, this doesn't make sense for a hotel, involves a complete remodel of the HVAC, and even requires me to re-model the secondary system (DOAS units), which IECC standard reference buildings don't usually do.

I know there is often leniency in interpretation, so if anyone has experience with this, please share. The ASHRAE 90.1 2016 standard reference HVAC system for a hotel in this climate zone is PTACs, which makes a lot more sense and would use the same DOAS units for the standard reference model. Additionally, if one could interpret the VRF system as "single-zone," then the IECC would require PTHPs as the standard reference HVAC system, which would also make sense.

Thanks in advance to anyone who can help!

Best, David

C:\fakepath\iecc snippet.png

IECC standard reference HVAC system for VRF/DOAS

Hi energy modelers,

I'm building an IECC (2018) standard reference building energy model for a hotel with an air-cooled heat recovery VRF/DOAS system. The HVAC system which I should seemingly use for the baseline model does not make sense to me, so I wanted to get some input.

According to the attached snippet of the "Commercial Buildings - Total Building Performance" section, the standard reference building should be modeled with System 3: VAV/electric resistance heat. However, this doesn't make sense for a hotel, involves a complete remodel of the HVAC, and even requires me to re-model the secondary system (DOAS units), which IECC standard reference buildings don't usually do.

I know there is often leniency in interpretation, so if anyone has experience with this, please share. The ASHRAE 90.1 2016 standard reference HVAC system for a hotel in this climate zone is PTACs, which makes a lot more sense and would use the same DOAS units for the standard reference model. Additionally, if one could interpret the VRF system as "single-zone," then the IECC would require PTHPs as the standard reference HVAC system, which would also make sense.

Thanks in advance to anyone who can help!

Best, David

C:\fakepath\iecc snippet.png