04191023 is referenced by 11 patents and cites 2 patents.

A heat pump is disclosed which has a compressor, an indoor condenser (for winter heating), outdoor evaporator (for winter heating) and piping for flowing a refrigerant between the compressor, the condenser and the evaporator. A second refrigerant loop is formed which bypasses the compressor and communicates with the condenser outlet and intake. A liquid metering pump flows liquid refrigerant from the outlet of the condenser via a fuel, e.g. liquid petroleum gas fired refrigerant vaporizer back to the condenser intake so that auxiliary heat from the burner for heating an indoor space by feeding to the condenser heated refrigerant vapor in addition to the refrigerant vapor supplied to the condenser by the compressor.

Title
Fuel fired supplementary heater for heat pump
Application Number
769830
Publication Number
4191023
Application Date
June 23, 1978
Publication Date
March 4, 1980
Inventor
Stephen E Veyo
Murrysville
PA, US
Francis J Sisk
Apollo
PA, US
Agent
Townsend and Townsend
Assignee
Electric Power Research Institute
CA, US
IPC
F25B 29/00
F25B 13/00
F25B 27/02
F25B 7/00
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