APPENDIX 7-A. RECS 2001 VARIABLES AND VALUES 

TABLE OF CONTENTS 

7-A.1	 INTRODUCTION .................................................................................................7-A-1


7-A.2	 SAMPLE DETERMINATION..............................................................................7-A-1


7-A.2.1 Water Heater ........................................................................................7-A-1


7-A.2.2 Direct Heating Equipment ...................................................................7-A-3


7-A.2.3 Pool Heaters.........................................................................................7-A-5


7-A.3	 RECS 2001 DATABASE VARIABLE DEFINITIONS .......................................7-A-7


LIST OF TABLES 

Table 7-A.2.1 Selection of RECS 2001 Records by Fuel Type: Water Heaters...............7-A-1 

Table 7-A.2.2 List of RECS 2001 Variables Used in Water Heaters ...............................7-A-2 

Table 7-A.2.3 Summary of Direct Heating Equipment Household Sample (RECS 

2001) ..........................................................................................................7-A-4 

Table 7-A.2.4 List of RECS 2001 Variables Used in Direct Heating Equipment ............7-A-5 

Table 7-A.2.5 Criteria for Selection of Pool Heaters Household Sample (RECS 2001)..7-A-6 

Table 7-A.2.6 List of RECS 2001 Variables Used in Pool Heaters..................................7-A-6 

Table 7-A.3.1 Definitions of RECS 2001 Variables Used in Life-Cycle Cost Analysis..7-A-7 

7-A-i 

EE-2006-STD-0129 and EERE-2006-BT-STD-0129 COMMENT 32.2
APPENDIX 7-A. RECS 2001 VARIABLES AND VALUES 

7-A.1 INTRODUCTION 

Using Microsoft ACCESS, DOE created a database containing a subset of the records 

1 and variables from DOE’s Energy Information Administration (EIA)’s RECS 2001. DOE used 

this RECS subset in the life-cycle cost (LCC) analysis of the Residential Water Heaters, Direct 

Heating Equipment, and Pool Heaters Rulemaking. This appendix explains the variable name 

abbreviations and provides definitions of the variable values. For the entire RECS 2001 dataset, 

refer to http://www.eia.doe.gov/emeu/recs/recs2001/publicuse2001.html. 

7-A.2 SAMPLE DETERMINATION 

7-A.2.1 Water Heater 

The subset of RECS records used for water heaters met all of the following criteria (see 

Table 7-A.2.1): 

1) Used a water heater as the primary source of heated water, 

2) Used one of four fuels (electricity, gas, LPG, or oil as a heating fuel), 

3) Provided heated water for only one housing unit, 

4) Had an indication of water heater size, 

5) Had energy consumption greater than zero. 

Table 7-A.2.1 Selection of RECS 2001 Records by Fuel Type: Water Heaters


Product Class Algorithm # of Records 

# of US Households 

Represented 

(million) 

Natural Gas FUELH2O = 1 or 2 

WHEATOTH = 0 

WHEATSIZ = 1 Or 2 Or 3 Or 6 

2220 52.2 

Electricity FUELH2O = 5 

WHEATOTH = 0 

WHEATSIZ = 1 Or 2 Or 3 Or 6 

1638 36.8 

Fuel Oil FUELH2O = 3 

WHEATOTH = 0 

WHEATSIZ = 1 Or 2 Or 3 Or 6 

107 1.7 

The RECS 2001 variables extracted for pool heaters are listed in Table 7-A.2.2


7-A-1 

EE-2006-STD-0129 and EERE-2006-BT-STD-0129 COMMENT 32.2
Table 7-A.2.2 List of RECS 2001 Variables Used in Water Heaters


Variable Description 

Location Variables 

REGIONC Census region 

DIVISION Census division 

LRGSTATE Large state designation 

LRG+DIV* Combined large state (LRGSTATE) and census division (DIVISION) 

CDD65 Cooling Degree-Days to base 65, 1-04 TO 12-04 

HDD65 Heating Degree-Days to base 65, 1-04 TO 12-04 

Household Characteristics Variables 

DOEID DOE 4-digit identification number 

NWEIGHT The Final Weight 

TYPEHUQ Type of Home: as report by Respondent 

YEARMADE Year Home Built 

NCOMBATH Number of Complete Baths 

FUELH2O Fuel used for heating water, washing or bathing 

WHEATOTH Main equipment also heat water for apartments 

WHEATSIZ Size of household's main water heater tank 

WHEATAGE How old is your household's main water heater 

NHSLDMEM How many people normally live in this household 

YEARS1 How many are infants under the age of 1 

YEARS2 How many are children between ages of 1 and 12 

YEARS3 How many are adults 65 or older 

YEARS5 How many are between ages 13 and 64 years old 

ATHOME Is someone at home all day on a typical weekday 

DISHWASH Does your household use an automatic dishwasher 

CWASHER Use a clothes washer in home 

PGASHTWA Who pays natural gas for hot water 

LPGPAY Who pays for bottled gas 

PELHOTWA Who pays electric for hot water 

7-A-2 

EE-2006-STD-0129 and EERE-2006-BT-STD-0129 COMMENT 32.2
FOPAY Who pays for fuel oil 

CELLAR Home Has Basement 

BASEHEAT Basement/crawl Space heated 

PRKGPLC1 Home has Garage or Carport 

CRAWL Home Has Crawl Space 

WELLPUMP Electric pump for well water 

WeatherDataCode* Not part of RECS, added to link to weather data (See App. F) 

TEMPHOME Setting During the day when someone is home 

TEMPGONE Setting During the day when no one is home 

TEMPNITE Setting During sleeping hours 

* Not part of RECS 2001 variables. 

7-A.2.2 Direct Heating Equipment 

The subset of RECS households used for direct heating equipment met all of the 

following criteria (see Table 7-A.2.3): 

1) Used floor/wall pipeless furnace, fireplace or heater as the primary or secondary source 

of heat, 

2) Used a heating fuel that is natural gas or liquefied petroleum gas (LPG), 

3) Heated only one housing unit, 

4) Primary fireplace equipment has a thermostat or secondary fireplace equipment has a flue 

vent, and 

5) Had energy consumption greater than zero. 

7-A-3 

EE-2006-STD-0129 and EERE-2006-BT-STD-0129 COMMENT 32.2
Table 7-A.2.3 Summary of Direct Heating Equipment Household Sample (RECS 2001)


Category Selection Criteria Fuel Type # of 

Records 

# of US 

Households 

Represented 

(million) 

Primary Equipment 

Floor/Wall 

Furnace 

EQUIPM = 6 

FUELHEAT = 1 Or 2 

HEATOTH = 0 

BTUNGSPH>0 or BTULPSPH>0 

Natural Gas 134 3.1 

LPG 11 0.2 

Room Heater EQUIPM = 7 

FUELHEAT = 1 Or 2 

HEATOTH = 0 

BTUNGSPH>0 or BTULPSPH>0 

Natural Gas 136 2.8 

LPG 53 1.1 

Fireplace EQUIPM = 9 

FUELHEAT = 1 Or 2 

HEATOTH = 0 

Number of Housing Units Heated = 1 

BTUNGSPH>0 or BTULPSPH>0 

THERMAIN = 1 

Natural Gas 5 0.1 

LPG 3 0.0 

Secondary Equipment 

Floor/Wall 

Furnace 

PIPELESS = 1 

PIPEFUEL = 1 or 2 

BTUNGSPH>0 or BTULPSPH>0 

Natural Gas 7 0.1 

LPG 9 0.1 

Room Heater ROOMHEAT = 1 

RMHTFUEL = 1 or 2 

BTUNGSPH>0 or BTULPSPH>0 

Natural Gas 47 0.9 

LPG 46 0.9 

Fireplace CHIMNEY = 1 

FPFUEL = 1 or 2 

BTUNGSPH>0 or BTULPSPH>0 

NGFPFLUE = 1 or 6 

Natural Gas 106 2.6 

LPG 21 0.4 

The RECS 2001 variables extracted for pool heaters are listed in Table 7-A.2.4


7-A-4 

EE-2006-STD-0129 and EERE-2006-BT-STD-0129 COMMENT 32.2
Table 7-A.2.4 List of RECS 2001 Variables Used in Direct Heating Equipment


Variable Description 

Location Variables 

REGIONC Census region 

DIVISION Census division 

LRGSTATE Large state designation 

LRG+DIV* Combined large state (LRGSTATE) and census division (DIVISION) 

CDD65 Cooling Degree-Days to base 65, 1-04 TO 12-04 

HDD65 Heating Degree-Days to base 65, 1-04 TO 12-04 

Household Characteristics Variables 

DOEID DOE 4-digit identification number 

NWEIGHT The Final Weight 

YEARMADE Year Home Built 

EQUIPAGE How old is equipment identified in D-2 heat system 

FUELUSE* Not part of RECS. Primary or secondary DHE energy consumption. 

FUEL TYPE* Not part of RECS. Primary or secondary DHE fuel type. 

SECONDARY EQP?* Not part of RECS. Assigns weather a household has primary or 

secondary DHE. 

ENERGY ADJ* Not part of RECS. Assigns weather a household with secondary DHE 

equipment needs an adjustment to the energy consumption. 

EQMAMT How much heat main heating equipment provides 

FUELHEAT Main fuel used for heating home 

* Not part of RECS 2001 variables. 

7-A.2.3 Pool Heaters 

The subset of records used to select a RECS household sample for pool heaters met all of 

the following criteria (see Table 7-A.2.5): 

1. Has a swimming pool, 

2. Used a pool heater to heat pool water, 

3. Used a heating fuel that is natural gas or liquefied petroleum gas (LPG), 

4. Heater provided heated pool water for only one housing unit. 

7-A-5 

EE-2006-STD-0129 and EERE-2006-BT-STD-0129 COMMENT 32.2
Table 7-A.2.5 Criteria for Selection of Pool Heaters Household Sample (RECS 2001)


By Fuel 

Type Selection Criteria # of Records # of US Households 

Represented (million) 

Natural Gas 

or propane 

FUELPOOL = 1 or 2 

BTUNGAPL> 0 or BTULPAPL >0 

41 1.0 

The RECS 2001 variables extracted for pool heaters are listed in Table 7-A.2.6. 

Table 7-A.2.6 List of RECS 2001 Variables Used in Pool Heaters 

Variable Description 

Location Variables 

REGIONC Census region 

DIVISION Census division 

LRGSTATE Large state designation 

LRG+DIV* Combined large state (LRGSTATE) and census division (DIVISION) 

CDD65 Cooling Degree-Days to base 65, 1-04 TO 12-04 

HDD65 Heating Degree-Days to base 65, 1-04 TO 12-04 

Household Characteristics Variables 

DOEID DOE 4-digit identification number 

NWEIGHT The Final Weight 

TYPEHUQ Type of Home: as report by Respondent 

YEARMADE Year Home Built 

SWIMPOOL Does your own swimming pool with filtering system 

POOL Is it a heated pool 

FUELPOOL What fuel is used most often to heat pool water 

RECBATH Does your home have a heated hot tub, spa 

FUELTUB What fuel is used to the water in hot tub, spa 

DRYRFUEL What fuel does clothes dryer use 

FUELFOOD Which fuels is used most for cooking 

OTHER APPLIANCE* Not part of RECS. Assigns whether a household has either gas cooking 

or gas clothes dryer appliances. 

BTUNGAPL Natural Gas Appliance Use 

7-A-6 

EE-2006-STD-0129 and EERE-2006-BT-STD-0129 COMMENT 32.2
BTUPAPL LPG Appliance Use 

AVG. DRYER-COOKING 

USE 

Not part of RECS. Assigns average gas cooking and/or dryer 

consumption. 

ADJUSTED FUEL USE Not part of RECS. BTUNGAPL or BTUPAPL minus AVG. DRYERCOOKING USE 

* Not part of RECS 2001 variables. 

7-A.3 RECS 2001 DATABASE VARIABLE DEFINITIONS 

The glossary below lists the variable names alphabetically. A brief explanation of the 

variable name as it appears in the database file follows the name. Table 7-A.3.1 provides the 

definitions of the variable’s values. 

Table 7-A.3.1 Definitions of RECS 2001 Variables Used in Life-Cycle Cost Analysis 

Variable Definition 

Location Variables 

REGIONC Census region 

1 = Northeast 

2 = Midwest 

3 = South 

4 = West 

DIVISION Census division 

1 = New England 

2 = Middle Atlantic 

3 = East North Central 

4 = West North Central 

5 = South Atlantic 

6 = East South Central 

7 = West South Central 

8 = Mountain 

9 = Pacific 

LRGSTATE Large state designation 

1 = New York 

2 = California 

3 = Texas 

4 = Florida 

7-A-7 

EE-2006-STD-0129 and EERE-2006-BT-STD-0129 COMMENT 32.2
LRG+DIV* Combined large state (LRGSTATE) and census division (DIVISION) 

1 = New England 

2 = Middle Atlantic (not including New York) 

3 = East North Central 

4 = West North Central 

5 = South Atlantic (not including Florida) 

6 = East South Central 

7 = West South Central (not including Texas) 

8 = Mountain 

9 = Pacific (not including California) 

10 = New York 

11 = California 

13 = Texas 

14 = Florida 

CDD65 Cooling Degree-Days to base 65, 1-04 TO 12-04 

Cooling degree days are the number of degrees the average daily 

temperature (ADT) is above the base temperature. 

HDD65 Heating Degree-Days to base 65, 1-04 TO 12-04 

Heating degree days are the number of degrees the ADT is below the 

base temperature. 

Household Characteristics Variables 

DOEID DOE 4-digit identification number 

TYPEHUQ Respondents reported type of home 

1 = Mobile Home 

2 = Single-Family Detached 

3 = Single-Family Attached 

4 = Apartment in Building containing 2-4 units 

5 = Apartment in Building containing 5 or more units 

YEARMADE Year home built 

1 = Before 1940 

2 = 1940-49 

3 = 1950-59 

4 = 1960-69 

5 = 1970-79 

6 = 1980 

7 = 1981-1989 

8 = 1990 

9 = 1991-1995 

10 = 1996-1998 

11 = 1999 

12 = 2000 

13 = 2001 

96 = Don't Know 

NWEIGHT Final weight 

Water Heater Variables 

7-A-8 

EE-2006-STD-0129 and EERE-2006-BT-STD-0129 COMMENT 32.2
TYPEHUQ Type of Home: as report by Respondent 

1 = Mobile Home 

2 = Single-Family detached 

3 = Single-Family Attached 

4 = Apartment in Building containing 2-4 units 

5 = Apartment in Building Containing 5 or more units 

NCOMBATH Number of Complete Baths 

FUELH2O Fuel used for heating water, washing or bathing 

1 = Natural gas from underground pipes 

2 = Bottled gas (LPG or propane) 

3 = Fuel oil 

4 = Kerosene 

5 = Electricity 

7 = Wood 

8 = Solar 

9 = District steam 

10 = Coal 

99 = No Answer/Not Applicable 

WHEATOTH Main equipment also heat water for apartments 

1 = Yes 

0 = No 

9 = No Answer/Not Applicable 

WHEATSIZ Size of household's main water heater tank 

1 = Small (30 gallons or less) 

2 = Medium (31 to 49 gallons) 

3 = Large (50 gallons or more) 

5 = Two separate water heaters 

0 = Don't have a separate water heater 

6 = Don't know 

9 = No Answer/Not Applicable 

WHEATAGE How old is your household's main water heater 

1 = Less than 2 years old 

2 = 2 to 4 years old 

3 = 5 to 9 years old 

4 = 10 to 19 years old 

5 = 20 years or older 

0 = Don't have a separate water heater 

96 = Don't know 

99 = No Answer/Not Applicable 

NHSLDMEM How many people normally live in this household 

1-15 = Number that live in household 

YEARS1 How many are infants under the age of 1 

0-15 = Number of infants under age 1 

YEARS2 How many are children between ages of 1 and 12 

0-15 = Number of children between 1 and 12 

YEARS3 How many are adults 65 or older 

0-15 = Number of adults 65 or older 

YEARS5 How many are between ages 13 and 64 years old 

0-15 = Remaining adults between 13 and 64 

7-A-9 

EE-2006-STD-0129 and EERE-2006-BT-STD-0129 COMMENT 32.2
ATHOME Is someone at home all day on a typical weekday 

1 = Yes 

0 = No 

6 = Don't know 

DISHWASH Does your household use an automatic dishwasher 

1 = Yes 

0 = No 

CWASHER Use a clothes washer in home 

0 = No 

1 = Yes 

PGASHTWA Who pays Natural gas for hot water 

1 = Household pays 

2 = Rent/Fee 

3 = Paid to third party 

6 = Household with gas wells on their property 

9 = No Answer/Not Applicable 

LPGPAY Who pays for bottled gas 

1 = Household pays 

2 = Rent/Fee 

3 = Paid to third party 

4 = Combined household bill 

9 = No Answer/Not Applicable 

PELHTWA Who pays electric for hot water 

1 = Household pays 

2 = Rent/Fee 

3 = Paid to third party 

6 = Household with gas wells on their property 

9 = No Answer/Not Applicable 

FOPAY Who pays fuel oil 

1 = Household pays 

2 = Rent/Fee 

3 = Paid to third party 

6 = Household with gas wells on their property 

9 = No Answer/Not Applicable 

CELLAR Home Has Basement 

0 = No 

1 = Yes 

9 = Not Applicable 

BASEHEAT Basement/crawl Space heated 

0 = None 

1 = All 

2 = Part 

9 = Not applicable 

PRKGPLC1 Home has Garage or Carport 

0 = No 

1 = Yes 

9 = Not Applicable 

7-A-10 

EE-2006-STD-0129 and EERE-2006-BT-STD-0129 COMMENT 32.2
CRAWL Home Has Crawl Space 

0 = No 

1 = Yes 

9 = Not Applicable 

WELLPUMP Electric pump for well water 

0 = No 

1 = Yes 

WeatherLocationCode* Not part of RECS, added to link to weather data (See App. F) 

TEMPHOME Setting During the day when someone is home 

40-94 = Temp when someone home 

95 = Heat turned off 

96 = Don't know 

97 = Did not live in unit last winter 

98 = Refused 

99 = No Answer/Not Applicable 

TEMPGONE Setting During the day when no one is home 

40-94 = Enter degrees Fahrenheit 

95 = Heat turned off 

96 = Don't know 

97 = Did not live in unit last winter 

98 = Refused 

99 = No Answer/Not Applicable 

TEMPNITE Setting During sleeping hours 

40-94 = Night temp 

95 = Heat turned off 

96 = Don't know 

97 = Did not live in unit last winter 

98 = Refused 

99 = No Answer/Not Applicable 

Direct Heating Equipment Variables 

FUELHEAT Main fuel used for heating home 

1 = Natural gas from underground pipes 

2 = Bottled gas (LPG or propane) 

3 = Fuel oil 

4 = Kerosene 

5 = Electricity 

7 = Wood 

8 = Solar 

9 = District steam 

10 = Coal 

99 = No Answer/Not Applicable 

7-A-11 

EE-2006-STD-0129 and EERE-2006-BT-STD-0129 COMMENT 32.2
EQUIPM Type of heating equipment provides the heat 

4 = Heat pump 

3 = Central warm-air furnace with ducts 

2 = Steam/hot water system with radiators 

5 = Built-in electric units installed in walls 

6 = Built-in floor/wall pipeless furnace 

7 = Built-in heater burning gas, oil, kerosene 

8 = Heating stove burning wood, coal, coke 

10 = Portable electric heaters 

11 = Portable kerosene heaters 

9 = Fireplace 

12 = Cooking stove used to heat and cook 

14 = Geothermal heat pump 

21 = Equipment not listed 

99 = No Answer/Not Applicable 

EQUIPAGE How old is equipment identified in D-2 heat system 

1 = Less than 2 years old 

2 = 2 to 4 years old 

3 = 5 to 9 years old 

4 = 10 to 19 years old 

5 = 20 years or older 

96 = Don't know 

99 = No Answer/Not Applicable 

PIPELESS Secondary Heating Equipment Built-in floor/wall pipeless furnace 

1 = Yes 

0 = No 

9 = No Answer/Not Applicable 

ROOMHEAT Secondary Heating Equipment Built-in room heater burning 

1 = Yes 

0 = No 

9 = No Answer/Not Applicable 

PIPEFUEL What fuel used in secondary pipelines furnace 

1 = Natural gas from underground pipes 

2 = Bottled gas (LPG or propane) 

4 = Kerosene 

5 = Electricity 

7 = Wood 

99 = No Answer/Not Applicable 

RMHTFUEL What fuel used in secondary room heater 

1 = Natural gas from underground pipes 

2 = Bottled gas (LPG or propane) 

3 = Fuel oil 

4 = Kerosene 

99 = No Answer/Not Applicable 

BTUNGSPH Natural gas space heat use estimated thousands of BTU 

9999999=Not Applicable 

BTULPSPH LPG space heat use estimated thousands of BTU 

9999999=Not Applicable 

7-A-12 

EE-2006-STD-0129 and EERE-2006-BT-STD-0129 COMMENT 32.2
EQMAMT How much heat main heating equipment provides 

1 = Almost all 

2 = About three-fourths 

3 = Close to half of all your heat 

6 = Don't know 

9 = No Answer/Not Applicable 

Pool Heater Variables 

SWIMPOOL Does your own swimming pool with filtering system 

0 = NO 

1 = Yes 

9 = No Answer/Not Applicable 

POOL Is it a heated pool 

0 = NO 

1 = Yes 

9 = No Answer/Not Applicable 

FUELPOOL What fuel is used most often to heat pool water 

1 = Natural gas from underground pipes 

2 = Bottled Gas (LPG or Propane) 

5 = Electricity 

8 = Solar 

99 = No Answer/Not Applicable 

BTUNGAPL Natural appliance use estimated thousands of BTU 

9999999=Not Applicable 

BTULPAPL LPG appliance use estimated thousands of BTU 

9999999=Not Applicable 

RECBATH Does your home have a heated hot tub, spa 

0 = No 

1 = Yes 

FUELTUB What fuel is used to the water in hot tub, spa 

1 = Natural gas from underground pipes 

2 = Bottled Gas (LPG or Propane) 

3 = Fuel oil 

5 = Electricity 

8 = Solar 

99 = No Answer/Not Applicable 

DRYRFUEL What fuel does clothes dryer use 

1 = Natural gas from underground pipes 

2 = Bottled Gas (LPG or Propane) 

5 = Electricity 

99 = No Answer/Not Applicable 

FUELFOOD Which fuels is used most for cooking 

1 = Natural gas from underground pipes 

2 = Bottled gas (LPG or propane) 

5 = Electricity 

99 = No Answer/Not Applicable 

* Not part of RECS 2001 variables. 

7-A-13 

EE-2006-STD-0129 and EERE-2006-BT-STD-0129 COMMENT 32.2
REFERENCES


1.	 U.S. Department of Energy - Energy Information Administration, Residential Energy 

Consumption Survey: 2001 Public Use Data Files, 2001. 

<http://www.eia.doe.gov/emeu/recs/recs2001/publicuse2001.html> 

7-A-14 

EE-2006-STD-0129 and EERE-2006-BT-STD-0129 COMMENT 32.2