GB2482563A

GB2482563A - Hot water heater inlet baffle

Info

Publication number: GB2482563A
Application number: GB1013327.0A
Authority: GB
Inventors: Michael John Perry
Original assignee: Baxi Heating UK Ltd
Current assignee: Baxi Heating UK Ltd
Priority date: 2010-08-06
Filing date: 2010-08-06
Publication date: 2012-02-08
Also published as: GB201013327D0

Abstract

A baffle 10 for a hot water heater has an elongate tubular body portion 11 closed at one end 12, with the open end being connectable to a cold water inlet and including slots 18 through the body portion. The baffle can be polypropylene for durability in the water tank, and around 100mm in length with an inner diameter of around 22mm. The baffle can be a push-fit, with slots depths between feet 17a,17b orientating the baffle.

Description

AN IMPROVED BAFFLE

Field of the Invention

The present invention relates to a baffle to alter the flow of a stream of water. In particular the baffle is for use in a water heater to direct incoming cold water.

Background to the Invention

In domestic water heaters, a body of water is heated and usually maintained at a predetermined temperature. When hot water is drawn off from the heater the water level within the heater drops until a predetermined value is reached. On reaching this level cold water, usually from a mains supply is admitted into the heater. If care is not taken then the cold water quickly mixes with the hot water to lower its temperature beyond that which would be acceptable. Although the whole volume of water is eventually heated up again to the original hot water temperature the user remains without adequately hot water.

In order to minimise this effect, many heaters are configured to minimise the mixing process. For example, baffles are frequently used which slow the water flow, or redirect the flow. An example of this is disclosed in UK Patent No. * 2333146. In that document incoming water is forced through a labyrinth to *I.SI * reduce the water's flow rate and alter the flow direction. ** * 25

* * Alternatively or additionally the cold water is led into the bottom of the water * heater, the cold water's greater density reducing the tendency for hot and cold to : mix. This facility is enhanced in that hot water is drawn off from the upper * portion of the heating. The problem is exacerbated where the water heater is one which is horizontally orientated, i.e. the width of the heater is greater than its height. In these types of boilers, the relative shallowness of the water increases the difficulties.

It is an object of the present invention to seek to address the above problems and to provide a baffle which reduces mixing between the hot and cold water.

Summary of the Invention

According to a first aspect of the invention there is provided a baffle for use in hot water heaters, the baffle having an elongate tubular body portion, closed at one end, a plurality of horizontally orientated elongate slots through said tubular body portion, the baffle being connected at the open end of the tubular body portion to a cold water inlet of a heater.

Without being limited by theory, it is believed that the horizontally orientated slots cause the incoming cold water to jet horizontally away from the baffle. In doing so the hot water in the tank is forced upwards due to its lower density resulting in layering of the water, each layer having water at a different temperature.

Preferably, the slots are arranged in two columns, which are further preferably on opposite sides of the body portion. The jets are believed to combine together to enhance the layering-effect.

* The body portion is optionally formed of polypropylene, for ease of manufacture * : * arid to provide a durable product. It is intended that the baffle should not require replacement during the lifetime of the heater.

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* 30 The body portion advantageously includes fixing means to connect the body * portion to the cold water inlet, said fixing means further advantageously consisting in a thickening of the rim of the open end of the body portion to form a ridge, the ridge being connected by a puslifit connection to the inlet. The connection is facilitated by the provision of slots which allows the resilient material of the body portion to bend; and subsequently return to their natural configuration.

The slots can also be of assistance in guiding the baffle into the correct orientation within the heater.

The typical length of a baffle is around 100mm, with an inner diameter of 22mm.

The dimensions of a typical slot are then around 15mm width and 3mm height.

The thickness of the walls is selected to give efficient jetting, and durability whilst keeping material costs low, but is typically around 1.6mm.

In a second aspect of the invention there is provided a water heater comprising a container body to retain water.

Brief Description of the Drawings

The invention is now described with reference to the accompanying drawings which show by way of example only: one embodiment of a baffle. In the drawings: Figures 1 a-ic are respectively a side view, a sectional along line A-A, and a top view; and * Figure 2 is a perspective view. * I

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* Detailed Description of the Invention *

*SI*SS * I The problem of preventing incoming cold water from mixing with the already- * S heated water within a water heater is well known. The problem is particularly acute in horizontally orientated heaters which are increasingly used to fit more ergonomically into spaces within smaller flats or other buildings. In such heaters, the shallower water depths used means that mixing occurs more readily.

Recently it has become increasingly recognised that layers of water at different temperatures can co-exist within a water heater with only a slow rate of heat transfer therebetween. The present invention seeks to exploit this although in a different maimer to that shown in the prior art. In addition the invention is made to be easily constructed and to be durable to continue functioning for the lifetime of the water heater. Moreover, the baffle is so designed to be easily and correctly installable.

Referring to the Figures, these show an embodiment of a baffle 10. The baffle 10 has a generally tubular cylindrical body 11 which is closed off at a distal end 12.

Fitment into a heater is provided through a clip-in or push fit arrangement. To facilitate this independent features of the baffle 10 co-operate together.

Firstly, a ridge 13 is provided at the base of the open proximal end 14 of the baffle 10. Following installation of the baffle 10, the upper edge surface 15 of the ridge 13, which is wider than the aperture in the water heater into which the baffle 10 is pushed acts to prevent movement of the baffle 10 and especially its removal. In addition, slots 1 6a, 1 6b are included, which increase the capacity of the feet sections 1 7a, I 7b to bend as the baffle 10 is pushed into position, allowing the ridge 13 to push past the aperture. Once through, the feet 1 7a, 1 7b revert back to their normal position so that the ridge 13 can prevent movement.

The slots can also be of assistance in ensuring that the baffle is orientated * * correctly within the heater, and that the slots face in the correct direction. To this * : ** end, the embodiment shown has two pairs of opposed slots of differing lengths, although having all slots the same length is within the scope of the invention.

*: * Typically the baffle 10 is formed of one piece of a plastics material, for example a polypropylene, which has the necessary resilient characteristics and is also * :* durable. A typical wall thickness which allows limited bending of the feet 17a, 17b is around 1.6mm.

The baffle 10 has a plurality of slots 18 formed in the tubular body 11. The slots 18 are approximately 15mm wide and 3mm in height to give a good flow pattern of water out of the baffle 10. In order to provide the required fluid flow out of the baffle 10, the slots 18 are arranged in two sets, each set having the same number of slots at the same distance along the tubular body 11, but each set being on the opposite side of the tubular body. Without being restricted to theory it is believed that the arrangement of slots causes water to flow out at relatively high velocity in a laminar flow. The cold water being denser remains in the bottom part of the heater, pushing the less dense water upwards. The laminar nature of the water flow reduces mixing of the warm and cold water.

The slots can also be arranged such that a slot on one side of the baffle has no counterpart on the other side of the baffle. For example in some heaters it is convenient for the baffle to be in a corner of the heater. In this case the slots should face into the bulk body of water. Were water to be directed against the wall of the heater then the flow within the heater could become turbulent.

Slots can be so arranged that a radial separation of for example 90°, 120° is achieved, where such an arrangement for example suits the characteristics of the heater.

In use therefore the baffle 10 is fitted into the end of a cold water supply pipe, such that water enters the open end of the baffle 10 as indicated by arrow B. Because the only way out of the baffle 10 is via the slots 18, and because water is * . e. *, * almost incompressible, the velocity of the water leaving through the slots 18 is * #.*S* * 25 higher than in the incoming water. The water issues from the baffle 10 in a plurality of jet flows. If the embodiment shown in the figures is employed in a * . horizontal water heater longer in one direction than the other perpendicular direction, then it is expected that the slots are directed along the longer direction. * ** * I * * I

It will of course be understood that the invention is not limited to the specific details described herein, which are given by way of example only, and that various modifications and alterations are possible within the scope of the invention. * I q

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Claims

CLAIMS1. A baffle (10) for use in hot water heaters, the baffle (10) having an elongate tubular body portion (11), closed at one end, a plurality of horizontally orientated elongate slots (1 6a, 1 6b) through said tubular body portion (11), the baffle (10) being connectable at the open end of the tubular body portion to a cold water inlet of a heater.
2. A baffle according to Claim 1 wherein the slots are arranged in two columns.
3. A baffle according to Claim 2, wherein the columns are on opposite sides of the body portion.
4. A baffle according to any preceding claim, wherein the body portion is formed of polypropylene.
5. A baffle according to any preceding claim, wherein the body portion includes fixing means to connect the body portion to the cold water inlet.
6. A baffle according to Claim 5, wherein said fixing means consists in a thickening of the rim of the open end of the body portion to form a ridge (13), the ridge being connected by a pushfit connection to the inlet.
7. A baffle according to Claim 5 or Claim 6 wherein the fixing means includes cut outs which allow the resilient material of the body portion to bend and subsequently return to its natural configuration.
8. A baffle according to any preceding claim, wherein the baffle is around 100mm in length.
9. A baffle according to any preceding claim having an inner diameter of around 22mm.
10. A baffle according to any preceding claim, wherein the dimensions of a slot are around 15mm width and 3mm height.
11. A baffle substantially as herein described with reference to and as illustrated by the accompanying drawings.
12. A water heater comprising a container body to retain water and including a baffle in accordance with Claim 1.