GB2479454A

GB2479454A - Water heating system for a motor caravan

Info

Publication number: GB2479454A
Application number: GB1105890A
Authority: GB
Inventors: Peter Redcliffe
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-02-08
Filing date: 2009-02-09
Publication date: 2011-10-12
Also published as: GB0802337D0; GB201105890D0; GB0902039D0; GB2457164A

Abstract

A water heating system for a motor caravan comprises a heat exchanger 11 and supply lines 12, 13 which are connected to an engine coolant system for the supply of hot water from the engine coolant system to the heat exchanger and subsequent return to the engine coolant system. A cold water supply tank 18 is provided with and a pump 19 for delivering cold water from the supply tank to the heat exchanger so that it flows through the heat exchanger in heat exchange relationship with the hot water supplied from the engine. The heated water is then supplied from the heat exchanger to a tap or shower 16. Preferably, the heat exchanger comprises a coil 14 where the volume of the coil makes up a significant proportion of the volume of the heat exchanger. A thermostatic control comprising a sensor 21 and a valve 22 may be provided for controlling the maximum temperature at which the water is supplied.

Description

WATER HEATING SYSTEMS AND METHODS OF PROVIDING HOT

WATER

Field of the Invention

This invention relates to water heating systems and to methods of providing hot water. The invention is particularly concerned with the provision of a water heating system for use in a motor caravan to provide hot water for a shower.

The storage tanks of conventional water heating systems are relatively large and are thus not appropriate for use in a motor caravan.

It is therefore an object of the present invention to provide an improved water heating system that has minimal space requirements.

A further object of the present invention is the provision of a water heating system that uses the engine of a motor caravan as a source of hot water.

A further object of the present invention is the provision of an improved method of providing hot water for supply to a tap or shower in a motor caravan.

Summary of the Invention

According to a first aspect of the present invention there is provided a water heating system for use in a motor caravan, the system comprising a heat exchanger, supply lines that can be connected to an engine coolant system of the motor caravan for the supply of hot water from the engine coolant system to the heat exchanger and subsequent return to the engine coolant system, a cold water supply tank, a line connecting the cold water supply tank to a tap or shower, a pump for delivering cold water from the cold water supply tank to the heat exchanger so that it flows through the heat exchanger in heat exchange relationship with the hot water in the heat exchanger, and a line connecting the heat exchanger to the tap or shower for the discharge of the heated water from the heat exchanger to the tap or shower.

The heat exchanger may comprise a coil and the dimensions of the coil and of the vessel within which it is contained are preferably such that the volume of the coil is a significant part of the volume of the vessel.

According to a second aspect of the present invention there is provided a method of providing hot water for supply to a tap or shower in a motor caravan, the method comprising providing a heat exchanger, connecting supply lines to the heat exchanger and to the coolant system of the engine of the motor caravan for the supply of hot water to the heat exchanger from the engine and for return to the engine, providing a cold water supply tank, operating a pump so as to supply cold water to the heat exchanger so that it flows through the heat exchanger in heat exchange relationship with the hot water supplied from the engine, providing a line connecting the heat exchanger to the tap or shower for the discharge of the heated water from the heat exchanger to the tap or shower, and providing a line connecting the cold water supply tank to the tap or shower for the supply of cold water to the tap or shower.

Brief Description of the Drawings

Figure 1 is a schematic view of a first embodiment of a water heating system for a motor caravan, Figure 2 is a schematic view of a second embodiment of the water heating system.

Description of the Preferred Embodiments

The water heating system shown in Figure 1 of the drawings draws its heat from the coolant circuit of an engine 10, namely an internal combustion engine of a motor caravan. The hot water from the engine 10 is supplied to a heat exchanger 11 along a line 13. The line 13 leads into the top of the heat exchanger 11 and returns to the engine 11 along a line 12 that extends from the bottom of the heat exchanger 11. The line 13 contains a pump 23 which will be running when the engine 10 is running. Although the points at which the lines 12 and 13 are connected to the heat exchanger 11 are shown in Figure 1 as being in line, in practice they will be located diametrically opposite one another.

The heat exchanger 11 comprises a tank that contains a multi-turn tubular coil 14 and, although the coil 14 is shown in the drawings as being a single coil, it may be a double coil, i.e. one coil within the other. Typical dimensions for the heat exchanger 11 are a diameter of mm and a height of 200 mm and the coil 14 is formed from tube of less than 20 mm such that there are of the order of ten turns of the coil 14, for example, between eight and twelve turns. The coil 14 thus occupies a significant part of the interior of the heat exchanger 11.

The coil 14 is connected by a line 15 to a tap or shower 16 and there is a line 17 leading from a cold water storage tank 18 for the supply of cold water to the base of the heat exchanger 11. Water is pumped from the storage tank 18 to the heat exchanger 11 by a pump 19 and there is also a line 20 for the optional supply of cold water from the storage tank 18 to the tap or shower 16.

There is a thermostatic control comprising a sensor 21 and a valve 22 for controlling the maximum temperature at which hot water can be supplied from the heat exchanger 11 to the tap or shower 16 and the thermostat may be adjustable in dependence on the requirements of the user.

In use, when the occupant of the motor caravan in which the heating system is installed wishes to have a shower, he or she will turn on the engine 10 and will run the engine 10 for a short period of time such as to generate a supply of hot water in the engine coolant system. He or she will then turn on the shower and will turn on the pump 19 -the pump 23 will also be running for as long as the engine is running. The cold water supplied from the cold water storage tank 18 will be supplied along the line 17 to the coil 14 of the heat exchanger II. The cold water passing through the coil 14 will travel a significant distance through the turns of the coil in heat exchange relationship with the hot water supplied from the engine 10 and will be heated to a temperature suitable for a shower before being supplied along the line 15.

The system shown in Figure 2 is similar to that shown in Figure I with two exceptions. The first is that the heat exchange element is a plate-type heat exchanger. The second is that the thermostatic control comprises an adjustable thermostatic mixer valve 24 which is incorporated in the line 15 from the tank 14 and is connected by a line to the cold water supply tank 18. The mixer valve 24 is adjustable and can be set so as to control the maximum temperature at which hot water is supplied to the tap or shower 16.

The volume occupied by the heat exchanger 11 is small and the tank can thus readily be accommodated in a motor caravan.

The pump 23 is a 12 volt electric pump and can be used to maintain the flow of hot water after the engine has been switched off and thus a continuous supply of hot water for the length of time that it typically takes to have a shower. On average, a volume of hot water of the order of five gallons will be provided, which is normally ample for showering.

The present invention permits the use of a hot internal combustion engine as a substitute for a hot water tank, thus eliminating the hot water tank from the system. The heat from the water obtained from the hot engine is transferred by the heat exchanger to cold water pumped from a cold water tank that is quite separate from the engine. "Instant" hot water for showering can thus be obtained in a motor caravan utilising the minimum amount of space.

Claims

Claims:- 1. A water heating system for use in a motor caravan, the system comprising a heat exchanger, supply lines that can be connected to an engine coolant system of the motor caravan for the supply of hot water from the engine coolant system to the heat exchanger and subsequent return to the engine coolant system, a cold water supply tank, a line connecting the cold water supply tank to a tap or shower, a pump for delivering cold water from the cold water supply tank to the heat exchanger so that it flows through the heat exchanger in heat exchange relationship with the hot water in the heat exchanger, and a line connecting the heat exchanger to the tap or shower for the discharge of the heated water from the heat exchanger to the tap or shower.
2. A water heating system as claimed in Claim 1, in which the heat exchanger comprises a coil.
3. A water heating system as claimed in Claim 2, in which the dimensions of the coil and of a vessel in which it is contained are such that the volume of the coil is a significant part of the volume of the heat exchanger.
4. A water heating system as claimed in any one of the preceding claims, in which there is a thermostatic control comprising a sensor and a valve for controlling the maximum temperature at which hot water can be supplied from the heat exchanger to the user.
5. A water heating system as claimed in Claim 4, in which the thermostat is adjustable in dependence on the requirements of the user.
6. A water heating system for a motor caravan substantially as hereinbefore described with reference to and as shown in the accompanying drawings.
7. A motor caravan having a water heating system as claimed in any one of the preceding claims.
8. A method of providing hot water for supply to a tap or shower in a motor caravan, the method comprising providing a heat exchanger, connecting supply lines to the heat exchanger and to the coolant system of the engine of the motor caravan for the supply of hot water to the heat exchanger from the engine and for return to the engine, providing a cold water supply tank, operating a pump so as to supply cold water to the heat exchanger so that it flows through the heat exchanger in heat exchange relationship with the hot water supplied from the engine, providing a line connecting the heat exchanger to the tap or shower for the discharge of the heated water from the heat exchanger to the tap or shower, and providing a line connecting the cold water supply tank to the tap or shower for the supply of cold water to the tap or shower.
9. A method of providing hot water for supply to a tap or shower in a motor caravan substantially as hereinbefore described with reference to the accompanying drawings.