05918668 is referenced by 12 patents and cites 9 patents.

A system (10) for increasing the temperature of air initially delivered by an existing heat pump system (100) is provided which may be easily added to the existing heat pump system. System (10) includes a heat pump comfort controller (12) having a plurality of control signal leads (14, 16, 18 and 20) which are coupled in parallel relationship with a respective plurality of control signal leads (114, 116, 118 and 120) of heat pump system (100) interconnecting the heat pump indoor unit (110) with the heat pump outdoor unit (112). Heat pump comfort controller (12) includes a thermostat (50) for sensing the outdoor ambient air temperature and includes a contact (52) that closes when the outdoor ambient temperature falls below a predetermined value, conducting a control signal from the lead (14) for signaling the energization of supplemental heating units (132) of heat pump system (100). System (10) also includes a duct thermostat (62) which senses the temperature of the main supply air duct (130) of heat pump system (100) for de-energizing the supplemental heating units when the main supply air duct temperature reaches a predetermined value.

Title
System for increasing the temperature of air initially delivered by a heat pump
Application Number
9/28494
Publication Number
5918668
Application Date
February 24, 1998
Publication Date
July 6, 1999
Inventor
Andrew M Trimble
13031 Bottom Rd., Hydes, 21082
MD, US
Agent
Rosenberg Klein & Bilker
IPC
G05D 23/00
F25B 29/00
View Original Source