GB2059036A

GB2059036A - Improvements in and relating to heat pump systems

Info

Publication number: GB2059036A
Application number: GB7932406A
Authority: GB
Original assignee: Sumner J A
Current assignee: Sumner J A
Priority date: 1979-09-19
Filing date: 1979-09-19
Publication date: 1981-04-15

Abstract

A heat pump heating system for transferring heat from a reservoir (12) of low temperature heat (12) e.g. the ground or water mass to an environment requiring higher temperature heat includes an evaporator coil (10) within the reservoir (12), a compressor unit (14), a condenser unit (18) located within the environment requiring heat and an expansion valve (22) or a length of capillary piping between the evaporator and condenser. The condenser coil (18) may be incorporated into the walls or flooring of a building or into a hollow apertured container situated within the building for a convective air flow over the condenser coil. <IMAGE>

Description

SPECIFICATION Improvements in and relating to heating systems Field of invention This invention concerns heating systems and in particular heating systems incorporating a heat pump for converting heat at one temperature into heat at another temperature and thereby transferring heat from a low temperature source such as the ground into a building requiring temperatures of the order of 1 6 to 20"C or more.

Background to the invention Previously proposed heat pump circuits require pumping power in either the evaporator or condenser circuits or both which may be equal to 20% or more of the driving motor input. This means additional power to be put into the heat pump circuit which of necessity reduces the efficiency of the circuit.

In many existing systems fans are also used to transfer air over the evaporator unit and sometimes also the condenser unit. Again power is required for driving these fans and the operation of the fans inevitably produces unwanted noise.

Object of the invention It is an object of the present invention to provide an alternative and improved heating system using a heat pump for transferring heat energy from a reservoir of lower grade heat to an environment requiring higher grade heat. Using the pressure difference which exists within a heat pump system.

The invention According to the present invention a heating system for transferring heat from a reservoir or lower temperature heat to an environment requiring higher temperature heat comprises an evaporator coil embedded in the reservoir of heat, a compressor unit and a condenser unit situated within the environment requiring heat with fluid conduit means between the coil in the lower grade heat reservoir and the compressor and between the compressor and the condenser and between the condenser and the evaporator coil, this last length of fluid conduit including or comprising a restriction to the flow of fluid medium therethrough so as to produce a significant pressure drop thereacross.

The reservoir may comprise soil or water or a combination thereof.

The environment may comprise for example a building such as a domestic dwelling.

The condenser coil may be incorporated into the walls or flooring of the building or alternatively may be incorporated into a hollow container situated within the building such that air can flow freely from below the container, through the container and in contact with the condenser coil located therein to leave the container at a high level after being heated by the transfer of heat from the condenser coil thereto during the passage of air through the container.

The restriction may comprise a capillary section of tubing between the condenser coil and evaporator coil or alternatively may comprise an expansion valve for performing the same function.

The condenser coil may in addition or alternatively be embedded in a bath of oil or water or located within a flooring slab typically of concrete.

The invention therefore provides for the circulation of hot refrigerant directly from a compressor unit through a condenser coil and from there through an expansion device to return it to the evaporator coil. The wall or floor or convector unit located within the building thus becomes part of the condenser and relies upon the temperature difference between the composite condenser surface and the surrounding medium receiving heat to cause condensation of the refrigerant within the condenser.

This is quite distinct from previous proposals for heat pump heating systems in which the refrigerant has been passed through a heat exchanger for heating another fluid medium such as air or water or oil which is then pumped through heat exchangers such as radiators or in the case of hot air directly into the environment requiring heat.

A system embodying the invention thus not only saves the additional heat exchangers and pumps and/or fans but also reduces the energy requirements to operate the system thereby producing for given size of compressor and for a given reservoir of heat and environment requiring heat, a more efficient system than has hitherto been possible.

The invention will now be described by way of example with reference to the accompanying drawing.

In the drawing Figure 1 is a diagrammatic view of a system embodying the invention, Figure 2 is another diagrammatic view of a system embodying the invention and Figure 3 is a diagrammatic view of an alternative condenser unit for use in the system of Fig. 2.

Detailed description of illustrated embodiments Fig. 1 shows an evaporator coil 10 embedded in soil or water designated by reference numeral 12. Piping connects one end of the coil 10 to the inlet of a compressor unit 1 4 the output of which delivers compressed refrigerant via a pipe 1 6 to one end of another coil 1 8 serving as part of the condenser unit of the heat pump system. A return flow pipe 20 connects the other end of the condenser coil 1 8 with the evaporator coil 10.

An expansion valve 22 is located along the length of the pipe 20 or alternatively (not shown) some or all of the pipe 20 is a capillary tube thereby producing a considerable pressure difference thereacross with passage of fluid therethrough.

The system operates so as to transfer heat from the soil or water reservoir 1 2 into the condenser coil 1 8 which thus becomes heated and dissipates heat to the immediate environmment of the condenser coil 1 8. To this end, in a domestic dwelling or similar building, the coil 1 8 is embedded in a concrete floor slab 24.

Alternatively (not shown) the coil 1 8 may be incorporated into the wall panels of a building.

Fig. 2 shows an alternative system in which an evaporator coil 30 is embedded in the ground or in a reservoir of water designated by reference numeral 32. The one end of the evaporator coil 30 delivers heated refrigerant to the input of compressor 34 via pipeline 36 and the compressed heated refrigerant is delivered by the compressor unit 34 along pipeline 38 to a case or panel containing air or oil or water designated by reference numeral 40.

The container 40 includes a coil 42 one end of which is connected to the pipeline 38 and the other end of which serves as the output from the container 40 and communicates via pipeline 44 and expansion valve 46 and further pipeline 48 with the other end of the evaporator coil 30.

Fig. 3 illustrates an alternative arrangement for the container 40 in which the coil 42 is located within a hollow box-like container having four side walls and top and bottom walls and in which the top and bottom walls are perforated as at 50 and 52 and the container is arranged so that the holes 50 and 52 are vertically above one another so that cool air can be drawn in through the holes in the floor of the box unit and after being warmed by the heat given off by the condenser coil 42, rises so as to pass out through the holes 50 for warming a room or other environment in which the unit is located.

Claims

1. A heating system for transferring heat from a reservoir of lower temperature heat to an environment requiring higher temperature heat comprising an evaporator coil embedded in the reservoir of heat, a compressor unit and a condenser unit situated within the environment requiring heat with fluid conduit means between the coil and lower grade heat reservoir and the compressor and between the compressor and condenser and between the condenser and the evaporator coil, this last length of fluid conduit including or comprising a restriction to the flow of fluid medium therethrough so as to produce a significant pressure drop thereacross.

2. A heating system as claimed in claim 1 in which the reservoir comprises soil or water or a combination thereof.

3. A heating system as claimed in claim 1 or 2 in which the said environment comprises a building such as a domestic dwelling.

4. A heating system as claimed in claim 3 wherein the condenser coil is incorporated into the walls or flooring of the building.

5. A heating system as claimed in claim 3 in which the condenser coil is incorporated into a hollow container situated within the building such that air can flow freely from below the container through the container and in contact with the condenser coil located therein to leave the container at a high level after being heated by the transfer of heat from the condenser coil thereto during the passage of air through the container.

6. A heating system as claimed in any of the preceeding claims wherein the restriction comprises a capillary section of tubing between the condenser coil and evaporator coil.

7. A heating system as claimed in claim 1 or 2 in which the condenser coil is embedded in a flooring slab.

7. A heating system as claimed in any of the preceeding claims 1 to 5 wherein the restriction comprises an expansion-valve between the condenser coil and evaporator coil.

8. A heating system as claimed in claim 3 wherein the condenser coil is embedded in a bath of oil or water.

9. A heating system as claimed in claim 3 in which the condenser coil is embedded in a flooring slab.

10. A heating system constructed arranged and adapted to operate substantially as herein described with reference to and as illustrated in Fig. 1 or Fig. 2 or Figs. 2 and 3 of the accompanying drawings.

CLAIMS (2 June 1980)

1. A heating system for transferring heat from a reservoir of lower temperature heat to an environment requiring higher temperature heat comprising an evaporator coil embedded in the reservoir of heat, a compressor unit and a condenser unit situated within the environment requiring heat with fluid conduit means between the coil and lower grade heat reservoir and the compressor and between the compressor and condenser and between the condenser and the evaporator coil, this last length of fluid conduit including or comprising a restriction to the flow of fluid medium therethrough so as to produce a significant pressure drop thereacross and wherein the condenser coil is incorporated into the walls or floor of a building.

3. A heating system as claimed in claim 1 or 2 which the condenser coil is incorporated into a hollow container situated within the building such that air can flow freely from below the container through the container and in contact with the condenser coil located therein to leave the container at a high level after being heated by the transfer of heat from the condenser coil thereto during the passage of air through the container.

6. A heating system as claimed in claim 1 or 2 wherein the condenser coil is embedded in a bath of oil or water.