How To Repair Electric kettles

The electric kettle is a very useful appliance and worth looking after, since you will only realize how much you rely on it when it breaks down. A regular check takes only a matter of minutes, while the length of time it takes to boil a pan of water on a cooker compared with the high speed electric kettle is quite enormous.

The working part of the kettle — the element — is available in different sizes, both in wattage and means of fitting. The higher the wattage, the faster the kettle boils — and the less electricity you use to boil the water. You will need to know the make and model number of your kettle as well as the diameter of the element fitting hole when buying replacements to ensure you get the right type, although adaptable elements are available.

Most spare parts can be readily obtained from electrical shops, although handles, lids and knobs may need to be ordered from individual manufacturers.

Wiring

Inspect the plug for loose connections and the kettle connector for evidence of overheating. Regularly check the flex for wear; at the first sign of deterioration, such as cracking or melting of the outer insulation, replace the flex with a new one of the correct rating.

Looking at the connector end of a standard kettle you will see a recessed screw. If you remove the screw, the outer part of the connector will slide down the flex and expose all the terminal screws and the clamping screws. Loosen all the screws so the flex can be withdrawn and replaced. Make sure the new flex is correctly fitted; if in any doubt, have it checked by an expert.

Connector

When replacing the flex, check for signs of burning or wear on the connector contacts. If the connector is worn, replace it at the same time; you can buy ready made-up leads with the connector attached. Burning on the live terminal of the connector is sometimes caused by the connector being removed from the kettle when the power is turned on. Every time this is done, a spark jumps between the live connection and the pin on the kettle element; this cannot usually be seen, but it does cause overheating to both the pin and connector. If you notice burning on the element pin, the element must be replaced before serious damage occurs.

Element

To change the element, first unscrew the shroud: behind this you will find a fibre washer. Remove both, lift off the lid and grasp the element from the inside; you will now be able to move and withdraw it from the inside of the body. Fit a rubber washer on the new element to provide a seal between the element and the kettle body; clean all traces of old washers and fur from the kettle, especially round the element hole. Place the fibre washer on the outside of the element before tightening the shroud. Test the kettle for leaks before using it again and, after one or two boilings which will slightly soften the rubber washer, tighten the shroud again. Repeat this operation whenever you have to change element washers or descale the kettle.

Feet

Feet are often damaged by placing the kettle on a hot surface such as a cooker. Most kettles have `push-on’ type feet which are easy to replace; if, however, a foot is knocked off along with its fixing stud, this is more difficult to replace. One company does make a foot repair kit; all you need to do is drill a small hole in the kettle base where the stud was fixed, insert a screw and washers from the inside of the kettle and onto this screw a new plastic foot with a threaded insert inside.

Spout

Leaks around the kettle spout are a serious problem since most adhesives do not form a permanent seal on chromium plating or aluminium: nor are they able to withstand the high temperatures of boiling water. The only sure remedy is to buy a new kettle or a new body.

Descaling kettle

All types of water heater are subject to furring. In the case of kettles, fur will increase the boiling time, cause automatic kettles to switch off prematurely due to excessive heat transference to the switch and could lead to failure of the switch unit as it melts from overheating. The kettle should be regularly de-scaled with a proprietary descaler which will dissolve the lime and fur; you can also try using a defurring device to prevent build-up of lime on the element.

Automatic types

Automatic kettles, which switch themselves off once the water has boiled, work on the principle that heat or steam from boiling water activates a cut-out or trips the switch to off. This avoids accidentally leaving the kettle to boil dry.

Heat-operated

Some kettles use temperature controlled devices in which the switch is activated by heat passing through the element. The preset thermal cut-outs work on pins or studs attached to the inside of the element: heat passing through these pins bends the thermal contact and shuts off power to the element. Although this is a safer mechanism than the steam-operated cut-outs, since steam does not enter the switch contact area, furring around the sensing area of the element can lead to overheating of the contacts and a reduction in the life of the kettle. If this happens you will have to replace the element as previously described.

Steam operated

With some kettles the steam travels along a tube to the bi-metal cut-out; care must be taken not to overfill the kettle since large amounts of water passing down the tube can damage the switch assembly. This type of kettle is usually identifiable by a small black switch unit with a neon light and a red button on top to activate the unit. The switch assemblies are preset and cannot be adjusted once fitted.

Changing switches

To change the switch you simply remove the single self-tapping screw and gently lift the switch, along with its sealing washer, away from the kettle. You will see the moving point or contact; as the switch button is pressed, the contact springs into position and pushes a glass rod down onto the leaf of the bi-metal strip. Extreme damp may cause the rod to seize up, which can result in the contact failing to reach the element pin and therefore not switch on; or the rod may stick in the downward position and so hold the switch to ‘on’. These defects cause overheating and the element may burn out. Should they occur, try to free the mechanism very carefully until, by pushing both button and bi-metal strip, the contact moves smoothly. If the kettle does not boil, check the condition and tension of the contact and bi-metal strip. If they are too slack, the slightest amount of steam will activate the mechanism and cause it to switch off prematurely; in this case you will have to replace the switch assembly.

Changing element seals

The element on an automatic kettle has a rubber seal inside the body and a fibre one on the outside. Instead of a shroud securing the element, as with standard kettles, a locking ring is used. This is a threaded collar with slots in it to take a special spanner; you can use a blunt screwdriver to tighten or loosen it, provided you are careful. If there is a cover tube over the steam pipe, take out the single screw which holds it in place before removing the element.

Don’t forget to test the kettle for leaks before fitting the switch assembly and check the condition of the element contact before reconnecting to the power. The element contact is small and must be kept clean and unpitted. Above the contact is a small bent contact for the neon light; if slightly displaced, the light will not work. In this case a slight repositioning of the neon light contact should correct the fault.

23. May 2011 by admin
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