GB2116688A

GB2116688A - Heat exchangers

Info

Publication number: GB2116688A
Application number: GB08307645A
Authority: GB
Inventors: George Hanson-Graville
Original assignee: DEEDMARK Ltd
Current assignee: DEEDMARK Ltd
Priority date: 1982-03-18
Filing date: 1983-03-18
Publication date: 1983-09-28
Also published as: GB8307645D0

Abstract

A heat exchanger mainly for domestic hot water supply is built up from six heat exchange units 1, each comprising an outer tube 2 and a coaxial inner tube 3 defining a passageway 4 therebetween for flow of water to be heated. The ends of the inner tubes 3 extend beyond the ends of the outer tubes 2 containing them and include couplings 5 serving either for connection with an inlet or outlet 6 for boiler flow and return, or for coupling with other inner tubes as at 7. <IMAGE>

Description

SPECIFICATION Heat exchangers This invention relates to heat exchangers and is primarily concerned with a domestic direct hot water heater whereby water heated by a boiler and flowing in a closed circuit is caused to transfer heat to water being consumed. In the more usual arrangement this is effected by a hot water heated coil located in a storage tank. This requires the whole mass of water in the tank to be brought to the required temperature and furthermore the tank is bulky. Domestic boiler systems are known using direct hot water supply wherein the boiler is adapted to heat the consumed water using an integral heat exchanger, but such arrangements cannot be applied to existing boiler installations principally intended for use with hot water storage tanks.

It is an object of this invention to provide a heat exchanger of compact construction for use with existing boilers and for direct hot water supply, which supply may be drawn from the mains and heated during flow. A further object is to provide a heat exchanger wherein the capacity can be adapted in a simple manner and which may be accommodated in existing unused spaced such as the side panel cavity of a bath.

According to this invention there is provided a heat exchanger assembly comprising a plurality of tubular heat exchange units, each formed by an outer tube and a coaxial inner tube the ends of which extend beyond the outer tube to include pipe couplings for connection with a water supply from a boiler or with a further heat exchange unit, the ends of the outer tube having fittings through which the inner tube passes and for passing water to be heated through the space formed between the two tubes, the end fittings including couplings for connection with a further unit or a water supply.

Preferably a plurality of such units are connected in series with the units extending in parallel relationship and encased in an insulating material to form a flat panel-like assembly. The couplings on the ends of the outer tube extend preferably at right angles to the tube, whereby two couplings on adjacent tubes may be connected when the tubes are in spaced parallel relationship. The couplings on the ends of the inner tubes may include elbow fittings whereby the fittings on adjacent tubes may be connected.

Advantageously the units may be fabricated from standard tubing and use standard fittings, for example the inner tube may be 15 mm copper piping and the outer tube 22 mm copper piping. An assembly of units, encased on foam, may be made in the form of a panel 50 mm thick, 500 mm high and 1400 mm long, which can then form a side panel of a bath.

Thus the heater can be accommodated in normally unused space. The invention thus also comprises in combination a bath and the heat exchanger as an integral unit.

Preferably the units are arranged in spaced parallel configuration and lying in a single plane. The units may be arranged in two planes lying in spaced parallel arrangement. This invention also embraces a system or installation for water heating embodying a boiler and the heat exchanger.

One embodiment according to the invention is shown in the accompanying drawings, wherein: Figure 1 shows a side elevation of a water heater construction, Figure 2 shows a section on A-A of Figure 1, and Figure 3 is a detail of the tube and connections.

Referring to the drawings, these illustrate a heat exchanger constructed as a domestic direct hot water system. The heat exchanger is built up from six heat exchange units 1, each comprising an outer tube 2 and a coaxial inner tube 3 defining a passageway 4 therebetween for flow of water to be heated. The ends of the inner tubes 3 extend beyond the ends of the outer tubes 2 containing them and include couplings 5 serving either for connection with an inlet or outlet 6 for boiler flow and return, or for coupling with other inner tubes as at 7.

The inner tubes are thus all in series and connected with the boiler supply. The ends of the outer tubes have fittings 8 provided with couplings 9 by which water may be conducted into and out of the passageways 4, these fittings providing serial connection for water flow through all the units from a feed 13 to a supply 14. The fittings used forthe various couplings may comprise standard elbows and tees, the inner tube 3 being conveniently 15 mm and the outer tube 222 mm diameter copper tubing.

The assembly of units 1 is conveniently housed within a foam insulation 10 forming a panel which can be housed in the side of a bath 11 and closed-off buy a conventional side panel 12.

The number of units may be varied according to needs and heat capacity, as may the length and configuration of the units 1.

The assembly shown may have more or less tubes according to capacity required and two banks of tubes may be provided in side by side coplanar relationship wherein all the connections may thus be positioned at the one corner of the assembly.

1. A heat exchanger assembly comprising a plurality of tubular heat exchange units each formed by an outer tube and a coaxial inner tube the ends of which extend beyond the outer tube to include pipe couplings for connection with a water supply from a boiler or with a further heat exchange unit, the ends of the outer tube having fittings through which the inner tube passes and for passing water to be heated through the space formed between the two tubes, the end fittings including couplings for connection with a further unit or a water supply.

2. A heat exchanger in accordance with Claim 1, wherein a plurality of units are connected in series with the units in parallel relationship and encased in an insulating material to form a flat panel-like assembly.

3. A heat exchanger in accordance with any preceding Claim, wherein the couplings on the ends of the outer tube extend at right angles to the tube whereby couplings on adjacent tubes may be connected together when the tubes are in spaced

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Heat exchangers This invention relates to heat exchangers and is primarily concerned with a domestic direct hot water heater whereby water heated by a boiler and flowing in a closed circuit is caused to transfer heat to water being consumed. In the more usual arrangement this is effected by a hot water heated coil located in a storage tank. This requires the whole mass of water in the tank to be brought to the required temperature and furthermore the tank is bulky. Domestic boiler systems are known using direct hot water supply wherein the boiler is adapted to heat the consumed water using an integral heat exchanger, but such arrangements cannot be applied to existing boiler installations principally intended for use with hot water storage tanks. It is an object of this invention to provide a heat exchanger of compact construction for use with existing boilers and for direct hot water supply, which supply may be drawn from the mains and heated during flow. A further object is to provide a heat exchanger wherein the capacity can be adapted in a simple manner and which may be accommodated in existing unused spaced such as the side panel cavity of a bath. According to this invention there is provided a heat exchanger assembly comprising a plurality of tubular heat exchange units, each formed by an outer tube and a coaxial inner tube the ends of which extend beyond the outer tube to include pipe couplings for connection with a water supply from a boiler or with a further heat exchange unit, the ends of the outer tube having fittings through which the inner tube passes and for passing water to be heated through the space formed between the two tubes, the end fittings including couplings for connection with a further unit or a water supply. Preferably a plurality of such units are connected in series with the units extending in parallel relationship and encased in an insulating material to form a flat panel-like assembly. The couplings on the ends of the outer tube extend preferably at right angles to the tube, whereby two couplings on adjacent tubes may be connected when the tubes are in spaced parallel relationship. The couplings on the ends of the inner tubes may include elbow fittings whereby the fittings on adjacent tubes may be connected. Advantageously the units may be fabricated from standard tubing and use standard fittings, for example the inner tube may be 15 mm copper piping and the outer tube 22 mm copper piping. An assembly of units, encased on foam, may be made in the form of a panel 50 mm thick, 500 mm high and 1400 mm long, which can then form a side panel of a bath. Thus the heater can be accommodated in normally unused space. The invention thus also comprises in combination a bath and the heat exchanger as an integral unit. Preferably the units are arranged in spaced parallel configuration and lying in a single plane. The units may be arranged in two planes lying in spaced parallel arrangement. This invention also embraces a system or installation for water heating embodying a boiler and the heat exchanger. One embodiment according to the invention is shown in the accompanying drawings, wherein: Figure 1 shows a side elevation of a water heater construction, Figure 2 shows a section on A-A of Figure 1, and Figure 3 is a detail of the tube and connections. Referring to the drawings, these illustrate a heat exchanger constructed as a domestic direct hot water system. The heat exchanger is built up from six heat exchange units 1, each comprising an outer tube 2 and a coaxial inner tube 3 defining a passageway 4 therebetween for flow of water to be heated. The ends of the inner tubes 3 extend beyond the ends of the outer tubes 2 containing them and include couplings 5 serving either for connection with an inlet or outlet 6 for boiler flow and return, or for coupling with other inner tubes as at 7. The inner tubes are thus all in series and connected with the boiler supply. The ends of the outer tubes have fittings 8 provided with couplings 9 by which water may be conducted into and out of the passageways 4, these fittings providing serial connection for water flow through all the units from a feed 13 to a supply 14. The fittings used forthe various couplings may comprise standard elbows and tees, the inner tube 3 being conveniently 15 mm and the outer tube 222 mm diameter copper tubing. The assembly of units 1 is conveniently housed within a foam insulation 10 forming a panel which can be housed in the side of a bath 11 and closed-off buy a conventional side panel 12. The number of units may be varied according to needs and heat capacity, as may the length and configuration of the units 1. The assembly shown may have more or less tubes according to capacity required and two banks of tubes may be provided in side by side coplanar relationship wherein all the connections may thus be positioned at the one corner of the assembly. CLAIMS

3. A heat exchanger in accordance with any preceding Claim, wherein the couplings on the ends of the outer tube extend at right angles to the tube whereby couplings on adjacent tubes may be connected together when the tubes are in spaced parallel relationship.

4. A heat exchanger in accordance with any preceding Claim, wherein the couplings in the ends of the inner tubes include elbow fittings, whereby the fittings of adjacent parallel tubes may be connected together.

5. A heat exchanger in accordance with any preceding Claim, wherein the tubular heat exchange units are arranged in spaced parallel configuration and lying in a single plane.

6. A heat exchanger in accordance with Claim 5, wherein the units are arranged in two planes lying in spaced parallel arrangement.

7. A heat exchanger in accordance with Claim 6, wherein the inlet and outlets for water supply and boiler feed are located adjacentlyata corner of the structure.

8. A heat exchanger substantially as described herein and illustrated.

9. An installation comprising a boiler in combination with a heat exchanger according to any preceding Claim.