GB2454689A

GB2454689A - Device to facilitate the heating of a liquid

Info

Publication number: GB2454689A
Application number: GB0722407A
Authority: GB
Inventors: Steve Barson
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-11-14
Filing date: 2007-11-14
Publication date: 2009-05-20
Also published as: GB0722407D0

Abstract

The device is connected to a new or existing hot water tank at the fixing point normally occupied by an immersion heater. Pipes pass through the device to provide a flow 13 and return 14 of water within the tank to and from a water heating means. The water heating means may be a solar water heating panel. The device may be a threaded cap 5 which screws into the fixing point. The device may also incorporate an electric immersion water heating element 15. The flow pipe may extend to a lower position in the tank than the return pipe. Several pipes may be included to provide a flow and return of water in the hot water tank to more than one means for heating water.

Description

Device to facilitate the heating of a liquid.

This invention relates to a device which allows the installation of a solar heat source or other heating source to an existing hot water tank or a new hot water tank.

When a solar water heating panel is added to an existing domestic hot water system, very often the entire existing hot water tank has to be changed to accommodate an additional heat exchanger in the tank, this is expensive, disruptive and wasteful of materials and time. An alternative method is to add additional connections to the existing pipe work to allow the water in the tank to be drawn off, heated, and returned to the tank. The existing methods require complicated plumbing operations, water systems to be drained down and involve the addition of pipe work which can restrict the flow of water. There is also an existing method which allows the fitting of an additional heat exchanger in the hole which is normally occupied by the electric immersion heater, the drawback with this method is that it is not very efficient at heating all the water in the tank and also means that the electric immersion heater is lost.

This invention overcomes the existing problems with providing solar water heating to a hot water tank by a device which incorporates pipes and an electric immersion heater in the same fitting, therefore allowing water in the tank to be drawn off for heating in the solar panel without losing the use of the electric immersion heater.

Many hot water tanks have an electric immersion heater. The element of the immersion heater usually passes through a threaded cap which is screwed into a threaded fitting in the upper portion of the tank, allowing the heating element to extend into the water and to heat that water when desired. These immersion heaters are removable by unscrewing the cap to allow replacement should the element ever fail and need replacing. This invention utilises this fitting point to provide a means of adding pipes which extend into the water in the tank.

In one aspect these pipes are connected to a solar water heating panel, although it is recognised that the device would work equally well if fitted to other water heating means such as a heat pump, solid fuel burning stove or other water heating device and is not limited to solar water heating. The device in this aspect has two pipes although any number could be used so long as they provided a flow and return for the liquid in the tank. For convenience, in this patent the flow' pipe shall indicate the pipe or pipes through which water is drawn from the tank, and the return' pipe shall be the pipe or pipes through which water is returned to the tank. By means of a pump, water is drawn from the tank and circulated through the solar panel, therefore increasing in temperature before returning to the tank.

In another aspect, several pipes could be fitted in the device, providing a flow and return for a number of different heating devices. For example a flow and return pipe for a solar water heater, a flow and return pipe for a heat pump etc. To facilitate maximum efficiency in the system, it is preferable though not essential, that the water is drawn through the flow pipe from the lower part of the tank. Due to stratification, the water at the bottom of the tank will generally be cooler than water at the top of the tank. Drawing water from the lower part of the tank means that more of the water in the tank is heated and the efficiency of the solar panel is greater.

So as to reduce disturbance of the stratification within the tank, it is preferred, though not essential, that the return pipe terminates at a position higher in the tank than the flow pipe. This heated water will tend to rise in the tank leaving the cooler water at the bottom.

It may be preferred to supply the device with both flow and return pipes longer than may be required. By doing this the user may cut off the pipes to the desired length for that particular application. This would provide a one size fits all' type of unit which would of course make stock holding and ordering far simpler.

It is also recognised that when this invention is used in conjunction with a solar water heating device, there is a reduction in the amount of materials, components and cost usually involved in the total installation of the solar heating apparatus. The reduced cost and simplicity makes the installation of a solar water heating system using this invention far simpler, less disruptive and more cost effective.

This invention will now be described by way of example, with reference to the accompanying drawings which illustrates the principal elements of the device in accordance with the invention.

Figure 1 shows the device and illustrates the threaded cap 5 which screws into the immersion heater fitting of a hot water tank. The electric immersion heater 15, the flow pipe 13, and the return pipe 14 are shown extending through the cap. The pipes and immersion heater are sealed into the cap to prevent water in the tank from leaking out.

Figure 2 shows an example of how the device may be configured within a conventional domestic hot water system. The hot water tank 16, is supplied via a pipe 19 with cold water from a header tank 17. Passing through the device's cap 5, is an immersion heater 15, a flow pipe 13, and a return pipe 14. Via sensors 7 and 20, a controller 3 monitors the temperature of the water in the tank 16, and in the solar water heating panel 12. When the controller commands, the pump 4 is activated via cable 21. This pump draws water from the tank through the flow pipe 13, circulates the water through the solar water heating panel 12, and returns the warmed water back to the tank via the return pipe 14.

Claims

Claims I. A device which facilitates a means for heating water to be connected to a new or existing hot water tank, where the device attaches to the fixing point normally occupied by the immersion heater, through which device passes pipes providing a flow and return of water within the tank to and from the water heating means.
2. A device which facilitates a means for heating water to be connected to a new or existing hot water tank where the device is a threaded cap which screws into the fixing point normally occupied by the immersion heater, through which cap passes pipes providing a flow and return of water within the tank to and from the water heating means.
3. A device as described in claims I or 2 which also incorporates an electric immersion water heating element.
4. A device as described in claim 1, 2 or 3 where the said means for heating water is a solar water heating panel.
5. A device as described in claim 1, 2, 3 or 4 where the flow pipe through which water is drawn from the tank extends to a lower position in the hot water tank than the return pipe.
6. A device as described in claims 1, 2, 3, 4 and 5 where several pipes are included to provide a flow and return of water in the hot water tank to more than one means for heating water.