Full Description

A total of 234 duty cycler controls were installed in residences in four Illinois locations in September of 1983. Duty cyclers are placed in the thermostat circuit and intermittently stop the normal burner cycle while the blower(or boiler pump) operates. No large-scale demonstration of residential duty cycler control devices had been performed previously. We present the savings potential for this device, for consideration as a supplement to federally funded weatherization.

The "PRISM" (Princeton Scorekeeping Method) computer program was used to determine house-by-house normalized annual consumption (NAC). Analysis was performed for a two year pre-installation period and for two succeeding years, separately and combined. Overall gas use change was approximately 4.4% to 5.4% by comparison of 93 test and 22 control houses which were previously weatherized. Approximately 35% of the test houses show a loss in energy efficiency.

A comfort survey was administered before duty cycler installation and again in the spring of 1984. The survey indicates that overall duty cycling increases comfort, although isolated occurrences of morning temperature recovery problems were noted.

Continued safe equipment operation was checked late in the winter of 1985. One hundred and nineteen inspections were performed by an independent firm. Equipment was judged to be in the same condition as comparable equipment not having duty cycler controls.

Duty cycling of residential heating burners has been demonstrated to save significantly less than some previous tests have shown and substantially less than the savings (e.g.," an average of 20% or more") some manufacturers have claimed. Duty cycling may play a role in weatherization; how ever, the installed cost must be less than $200 to provide cost-effectiveness equivalent to other mechanical system retrofits in Illinois. The technical and economic feasibility of combining duty cycling with other mechanical retrofits has not been determined.

Units: I-P

Citation: Symposium, ASHRAE Transactions, 1987, vol. 93, pt. 1, New York, NY

Product Details

Published: 1987 Number of Pages: 19File Size: 1 file , 1.9 MB Product Code(s): D-NY-87-19-1