In the detail screens of the Home Energy Saver, users can
modify the water heater characteristics to more closely simulate their
equipment and it’s usage. Table 13 shows the range of values for the inputs
previously mentioned and lists other characteristics (and their range of
values) that users can modify.
Table 13. User Inputs for Water
Heaters (Detailed Inputs Level)
|
Variable Name
|
Range of Possible Values
|
Default Value
|
Modeling Treatment
|
|
Fuel
|
Electric
Natural Gas
Liquid Propane Gas (LPG)
Fuel Oil
|
Varies by climate zone
|
|
|
Type
|
Separate from heating system
|
Separate
|
Water heater
energy calculated using process described in this section
|
|
Combined boiler, tankless
|
|
Water heating
energy calculated by DOE-2
|
|
Combined boiler, storage tank
|
|
|
Adult at Home
during weekdays
|
Yes
No
|
Varies by climate zone
|
|
|
Energy Factor
|
0 – 1.0
|
See Table 12
|
|
|
Recovery
Efficiency
|
0 – 1.0
|
See Table 11
|
|
|
Rated Input
|
0 – 99,000 (kWh, Btu/hr)
|
See Table 11
|
|
|
Tank Size
(gallons)
|
0 – 500
|
See Table 11
|
|
|
Thermostat
setting
|
Low (110 °F)
Medium-Low (120 °F)
Medium (130 °F)
Medium-High (140 °F)
High (150 °F)
|
Medium-Low
(120 °F)
|
|
|
Location
|
Basement or Crawlspace
|
Garage |
Tamb=(Tindoors+Toutdoors)/2
|
|
Garage
|
Tamb= Toutdoors
|
|
Indoors
|
Tamb= Tindoors; standby losses sent to
DOE2 as internal gains
|
|
Outdoors
|
Tamb= Toutdoors
|
Note: Tamb = annual average air
temperature around water heater (°F)
Tindoors = 67.5 ˚F
Toutdoors = average
outdoor air temperature from weather tape data
| 