04381549 is referenced by 177 patents and cites 7 patents.

Microprocessor controlled apparatus is provided for automatically diagnosing faults in a heat pump system. Temperature sensors located at strategic points in the system are read periodically in accordance with a preprogrammed diagnostic routine. Temperature measurements preferably representing comparison of two temperature readings that produce temperature differentials outside pre-established tolerance limits are stored with a fault identification representative of the corresponding fault measurement. A service technician can read the fault data from storage by activation of control means for that purpose whereby the nature of the causative fault or faults can readily be determined.

Title
Automatic fault diagnostic apparatus for a heat pump air conditioning system
Application Number
6/196412
Publication Number
4381549
Application Date
October 14, 1980
Publication Date
April 26, 1983
Inventor
Rollie R Herzog
Louisville
KY, US
Custis L Stamp Jr
Tyler
TX, US
Assignee
Trane CAC
WI, US
IPC
G01M 19/00
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