PHOTO REQUIRED of Water Heating System nameplate/model number per HERS® Standards Chapter 9. Raters/RFIs are responsible for documenting reasons for missing photos. For water heating systems, confirm that water heater types, fuel types, energy factors, recovery efficiencies, tank size, tank insulation, locations, and number of units which are entered into the software correspond with field-verified plans and/or field data collected by the Rater/RFI for the actual condition of the rated home.
- Energy Factor or UEF are generally found from manufacturer specs, AHRI, or ENERGY STAR databases.
- DHW tank size (gallons) can generally be captured from nameplate information.
- Location of the DHW equipment can affect the efficiency of the distribution system.
SCORING: (These errors are assessed per Water Heating System; the same error can occur multiple times if there are multiple Water Heating Systems and should be added to the overall total) "Satisfactory": When all mandatory photos are provided, and no errors in modeling "1": one to two minor errors in water heating modeling (listed below) (this is per modeled system) "2": three to four minor errors (listed below) in water heating modeling OR one to two major errors in water heating modeling (this is per modeled system) "3": Incorrect number of units OR five or more minor errors (listed below) OR three or more major errors in water heating modeling (listed below) (this is per modeled system) "Missing Photo": One or more of the mandatory photos are missing, and no errors in modeling "Missing Photo + "1": One or more of the mandatory photos are missing, plus "1" per scoring above "Missing Photo + "2": One or more of the mandatory photos are missing, plus "2" per scoring above "Missing Photo + "3": One or more of the mandatory photos are missing, plus "3" per scoring above
GUIDANCE: Minor Water Heating Modeling Errors:
- Modeled EF/UEF value off by 0.01 to 0.03 from AHRI Certificate or supporting docs (If UEF is listed on backup, ensure Rater or RFI converted to EF correctly)
- Modeled water tank capacity off by 3 gal to 5 gal from AHRI Certificate or supporting docs
- Modeled input capacity off by 3 kBtu/h to 5 kBtu/h from AHRI Certificate or supporting docs
- Modeled Recovery Efficiency is off by 3% to 5% from AHRI Certificate or supporting docs
- Modeled First Hour Rating [gal] is off by 2 gal to 3 gal from AHRI Certificate or supporting docs
- Modeled Max GPM [gpm] is off by .2 gal to .3 gal from AHRI Certificate or supporting docs
- % Water Heating Load Served off by 3% to 5%
- Incorrect location identified for Water Heating System Major Water Heating Modeling Errors:
- Incorrect equipment type identified
- Incorrect fuel type identified
- Modeled EF/UEF value off by greater than 0.03 from AHRI Certificate or supporting docs (If UEF is listed on backup, ensure Rater or RFI converted to EF correctly)
- Modeled water tank capacity off by greater than 5 gal from AHRI Certificate or supporting docs
- Modeled input capacity off by greater than 5 kBtu/h from AHRI Certificate or supporting docs
- Modeled Recovery Efficiency is off by greater than 5% from AHRI Certificate or supporting docs
- Modeled First Hour Rating [gal] is off by greater than 3 gal from AHRI Certificate or supporting docs
- Modeled Max GPM [gpm] is off by greater than .3 gal from AHRI Certificate or supporting docs
- % Water Heating Load Served off by greater than 5%
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