04112705 is referenced by 23 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
5/769830
Publication Number
4112705
Application Date
February 18, 1977
Publication Date
September 12, 1978
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
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