Patents by Inventor Bradley D. Caldwell

Bradley D. Caldwell has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Heat recovery ventilator with defrost
    Patent number: 7942193
    Abstract: A defrost system for a heat recovery ventilator/energy recovery ventilator (HRV/ERV), uses the interior space supply air of an integrated fan coil for defrosting a HRV/ERV core without creating negative pressure in the interior space, which wastes energy, without need of an external fifth port from which to draw defrost air from the interior space, which increases costs, and without re-circulating exhaust air into the interior space. During the defrost cycle, automatically controlled dampers close off the fresh air and exhaust air inputs, and exhaust output, and circulate supply air through the heat exchange core and into to the living space.
    Type: Grant
    Filed: November 20, 2008
    Date of Patent: May 17, 2011
    Assignee: Nu-Air Ventilation Systems Inc.
    Inventor: Bradley D. Caldwell
  • HEAT RECOVERY VENTILATOR WITH DEFROST
    Publication number: 20090133851
    Abstract: A defrost system for a heat recovery ventilator/energy recovery ventilator (HRV/ERV), uses the interior space supply air of an integrated fan coil for defrosting a HRV/ERV core without creating negative pressure in the interior space, which wastes energy, without need of an external fifth port from which to draw defrost air from the interior space, which increases costs, and without re-circulating exhaust air into the interior space. During the defrost cycle, automatically controlled dampers close off the fresh air and exhaust air inputs, and exhaust output, and circulate supply air through the heat exchange core and into to the living space.
    Type: Application
    Filed: November 20, 2008
    Publication date: May 28, 2009
    Inventor: Bradley D. Caldwell