NAME: Furnace TYPE: Observational Study SIZE: 90 observations, 10 variables DESCRIPTIVE ABSTRACT: Wisconsin Power and Light studied the effectiveness of two devices for improving the efficiency of gas home-heating systems. The electric vent damper (EVD) reduces heat loss through the chimney when the furnace is in its off cycle by closing off the vent. It is controlled electrically. The thermally activated vent damper (TVD) is the same as the EVD, except that it is controlled by the thermal properties of a set of bimetal fins set in the vent. Ninety test houses were used, 40 with TVDs and 50 with EVDs. For each house, energy consumption was measured for a period of several weeks with the vent damper active and for a period with the damper not active. This should help show how effective the vent damper is in each house. Both overall weather conditions and the size of a house can greatly affect energy consumption. A simple formula was used to try and adjust for this. Average energy consumed by the house during on period was recorded as (consumption)/[(weather)(house area)], where consumption is total energy consumption for the period, measured in BTUs, weather is measured in number of degree days, and house area is measured in square feet. In addition, various characteristics of the house , chimney, and furnace were recorded for each house. A few observations were missing and recorded as NA. SOURCES: Ryan, B.F. and Joiner, B.L. Minitab Handbook, 3rd edition. Page A-4. VARIABLE DESCRIPTIONS: 1. Type: Type of furnace (1 = forced air, 2 = gravity, 3 = forced water) 2. CHArea: Chimney area 3. CHShape: Chimney shape (1 = round, 2 = square, 3 = rectangular) 4. CHHeight: Chimney height 5. CHLiner: Type of chimney liner (0 = unlined, 1 = tile, 2 = metal) 6. House: Type of house (1 = ranch, 2 = two-story, 3 = tri-level, 4 = bi-level, 5 = one and one-half stories) 7. Age: House age in years (99 means 99 or more years) 8. BTUIn: Average energy consumption with vent damper active 9. BTUOut: Average energy consumption with vent damper inactive 10. Damper: Type of damper (1 = EVD, 2 = TVD)