Patents Represented by Law Firm Barnes, Kisselle, Raisch, Choate, Whittemore & Eulbert
  • Control for dual heating system including a heat pump and furnace
    Patent number: 5259445
    Abstract: A programmable thermostat is provided for the selective operation either of a fossil fuel furnace or a heat pump. The thermostat is programmed to operate the fossil fuel furnace when the outside temperature is below a preselected temperature range, and to operate the heat pump when the outside temperature is above the preselected temperature range. Within the preselected temperature range, the fossil fuel furnace may be operated during certain time periods and the heat pump may be operated during other time periods.
    Type: Grant
    Filed: July 13, 1992
    Date of Patent: November 9, 1993
    Assignee: The Detroit Edison Company
    Inventors: Robert G. Pratt, Lawrence A. Kasik, William S. Gianino