HVAC Distribution

In HPXML multiple HVACDistribution elements can be associated with a heating or cooling system. For the purposes of this translator, it is required that only one HVACDistribution element be linked. That element can then describe a ducted system, a hydronic system, or an open ended other system. For the translation to HEScore, only HVACDistribution elements that are ducted are considered.

Duct Location Mapping

For each Ducts element in each air distribution system, the location of the duct mapped from HPXML enumerations to HEScore enumerations according to the following mapping.

Duct Location mapping
HPXML HEScore
conditioned space cond_space
unconditioned space not translated
unconditioned basement uncond_basement
unvented crawlspace unvented_crawl
vented crawlspace vented_crawl
crawlspace not translated
unconditioned attic uncond_attic
interstitial space not translated
garage vented_crawl
outside not translated

Warning

If an HPXML duct location maps to not translated above, the translation for the house will fail.

Duct Fractions

For each Ducts element in an air distribution system the FracDuctArea is summed by HEScore duct location.

Duct Insulation

If the any of the Ducts elements in a particular location have a DuctInsulationRValue or DuctInsulationThickness that is greater than zero, all of the ducts in that location are considered insulated.

Duct Sealing

Duct leakage measurements are not stored on the individual Ducts elements in HEScore, which means they are not directly associated with a duct location. They are instead associated with an AirDistribution element, which can have many ducts in many locations. Duct sealing information is therefore associated with all ducts in an AirDistribution element.

To specify that the ducts in an AirDistribution system are sealed, the translator expects to find either of the following elements:

  • DuctLeakageMeasurement/LeakinessObservedVisualInspection element with the value of “connections sealed w mastic”.
  • HVACDistribution/HVACDistributionImprovement/DuctSystemSealed element with the value of “true”.

The DuctLeakageMeasurement can hold values for actual measurements of leakage, but since HEScore cannot do anything with them, they will be ignored. Therefore the following will result in an “unsealed” designation:

<DuctLeakageMeasurement>
   <DuctType>supply</DuctType>
   <!-- All of this is ignored -->
   <DuctLeakageTestMethod>duct leakage tester</DuctLeakageTestMethod>
   <DuctLeakage>
       <Units>CFM25</Units>
       <Value>0.000000001</Value><!-- exceptionally low leakage -->
   </DuctLeakage>
</DuctLeakageMeasurement>

and the following will result in a “sealed” designation:

<DuctLeakageMeasurement>
   <DuctType>supply</DuctType>
   <LeakinessObservedVisualInspection>connections sealed w mastic</LeakinessObservedVisualInspection>
</DuctLeakageMeasurement>