Both the Base and Improved home are fully instrumented with a Campbell Scientific CR10 data logger (see photo below) to both measure weather and thermal conditions as well as total electrical load and to isolate each of the major end-use loads. The data logger is connected to a AM416 multiplexer which allows the collection of a large number of analog measurements. A SW8A pulse count board allows storage of the numerous switch-closure measurements on site. A series of Ohio Semitronics watt-hour transducers measure the power consumption of the various appliances. The following electrical end-uses are individually metered: Total electricity, Air conditioner, Air handler, Hot water, Refrigerator, Range, Dryer, Washing Machine.

Miscellaneous loads, including lighting and ceiling fan use are tracked by subtracting the major electrical end uses from total.

In addition, a weather tower was installed to obtain data on ambient air temperature, relative humidity and solar irradiance. Wind speed is obtained by an RM Young anemometer; solar irradiance is obtained from Li-cor silicon cell pyranometers. Ambient and indoor relative humidities are taken by Vaisala hygrometers. Temperatures were taken in a variety of locations throughout both homes to characterize thermal performance. All temperatures are taken with Type-T thermocouples (0.1F accuracy):

• Ambient air temperature
• Attic air temperature
• Interior air temperature by thermostat
• Return air temperature (just before the coil)
• Supply air temperature (just after the coil)
• Supply air temperature at closest register
• Supply air temperature at far register

The temperatures taken before and after the air conditioner coil allow characterization of cooling system performance; the temperatures taken at the near and far registers should allow assessment of heat gains to the duct systems.

All of the data channels in both houses are scanned every ten seconds with integrated averages output to storage each 15-minutes. The resulting data is then sent to FSEC over dedicated telephone lines each evening. Detailed plots are created for each day of the monitoring project.