skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Heat pump using solar and outdoor air heat sources

Abstract

A heat pump system uses a non-reversing refrigeration circuit having a water-cooled condenser and a counterflow chiller fed by a thermostatic expansion valve to permit operation at close to zero superheat. To protect the compressor in the refrigeration circuit from possible flood-back at this low superheat, a combination suction-liquid heat exchanger-suction accumulator is employed. A hold-back valve serves to maintain constant compressor suction pressure regardless of evaporator pressure fluctuations caused by changing chiller fluid temperatures. The system is designed to operate in four distinct modes: (1) water source heat pump heating; (2) direct solar heating; (3) air source heat pump heating; and (4) heat pump cooling. To switch the refrigeration circuit to heat pump mode from the cooling mode or vice versa, four three-way valves and three fluid pumps are selectively operated. The fluid circuit of the system consists of two separate coils in an air-handling unit. One coil is connected to the solar collector circuit and may be used for either heating or cooling. A second coil is connected to the condenser circuit and works during the heat pump cycle.

Inventors:
Publication Date:
OSTI Identifier:
6536730
Patent Number(s):
US 4363218
Assignee:
Halstead Ind Inc
Resource Type:
Patent
Resource Relation:
Patent File Date: Filed date 10 Apr 1981; Other Information: PAT-APPL-252799
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; HEAT PUMPS; SOLAR REFRIGERATION; ACCUMULATORS; CONDENSERS; HEAT EXCHANGERS; HEAT TRANSFER FLUIDS; PUMPS; SOLAR EQUIPMENT; VALVES; CONTAINERS; CONTROL EQUIPMENT; COOLING; EQUIPMENT; FLOW REGULATORS; FLUIDS; REFRIGERATION; TANKS; 140909* - Solar Thermal Utilization- Miscellaneous Solar Applications- (1980-)

Citation Formats

Nussbaum, O J. Heat pump using solar and outdoor air heat sources. United States: N. p., 1982. Web.
Nussbaum, O J. Heat pump using solar and outdoor air heat sources. United States.
Nussbaum, O J. Tue . "Heat pump using solar and outdoor air heat sources". United States.
@article{osti_6536730,
title = {Heat pump using solar and outdoor air heat sources},
author = {Nussbaum, O J},
abstractNote = {A heat pump system uses a non-reversing refrigeration circuit having a water-cooled condenser and a counterflow chiller fed by a thermostatic expansion valve to permit operation at close to zero superheat. To protect the compressor in the refrigeration circuit from possible flood-back at this low superheat, a combination suction-liquid heat exchanger-suction accumulator is employed. A hold-back valve serves to maintain constant compressor suction pressure regardless of evaporator pressure fluctuations caused by changing chiller fluid temperatures. The system is designed to operate in four distinct modes: (1) water source heat pump heating; (2) direct solar heating; (3) air source heat pump heating; and (4) heat pump cooling. To switch the refrigeration circuit to heat pump mode from the cooling mode or vice versa, four three-way valves and three fluid pumps are selectively operated. The fluid circuit of the system consists of two separate coils in an air-handling unit. One coil is connected to the solar collector circuit and may be used for either heating or cooling. A second coil is connected to the condenser circuit and works during the heat pump cycle.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1982},
month = {12}
}