Where the white meter tariff is in operation it can be an advantage to heat the full contents of a tank overnight when the cheaper rate for electricity is in force and switch on the short element wizen additional hot water is needed.
This normally requires two circuits for the immersion heater installation. One circuit is used for the night rate supply, when time controlled in conjunction with night storage heaters, this supplying the long element of a dual immersion heater or the lower immersion heater of a two- immersion heater arrangement. Read the rest of this entry »
Electric heating of water can be carried out in a variety of ways. These include small capacity heaters fitted above the sink, instantaneous sink heaters or immersion heaters in the hot water tank.
Small storage water heaters fitted over the sink or washbasin having capacities of up to about 3 gallons and electrical loadings of 1 to 3 kW are usually supplied from the ring circuit by means of a spur. Except in a bathroom, the outlet can be a fused plug and switched socket-outlet, preferably with neon indicator. Read the rest of this entry »
These have a similar motor to the vacuum cleaner; the most common fault being brush wear. Burning out of the windings is also fairly frequent and is usually caused by overloading due to misuse.
The popular low-priced rotary mowers are usually powered by a brush motor similar to that of an electric drill (power tool). Carbon brushes need replacing when they wear but the component which is likely to give the greatest concern is the thermal cutout usually situated in the handle. The function of this is to cut off the current to the motor when there is a risk of overload when cutting very long grass. Read the rest of this entry »
The earth path of an appliance can be checked easily using a simple test meter. Remember, path of low resistance is required from all items within a appliance that are linked into the earth path via the yellow and green cable.
The earth path of an appliance from its exposed metal parts to the earth pin of the plug should be a maximum of 1 ohm (BS3456).
Checking the earth path of a socket requires an earth loop test meter which needs to be operated correctly. This is an expensive item and, moreover, problems may be encountered with distribution boards fitted with an RCD. It is, therefore, advisable to have these tests done by a qualified electrical contractor. Read the rest of this entry »
The humble kettle has been given a new image in recent years. Simple versions consisting of only a container with a heating element fixed inside are still available, but for many years the trend has been towards the automatic kettle that turns off once the water has boiled.
Some more recent models have been further improved with high-speed elements and spout filling. The latest jug version combines all the features of a modern kettle with the added feature of the handle’s being positioned on the side, so that the user avoids the steam when pouring.
As with irons, cable damage through wear and tear and misuse tends to be a common fault. Cordless kettles and jugs preempt this problem. They are similar to cordless irons in that they require a power base that has its own mains lead. When the cordless kettle is placed on its base, electrical contact is made to its heating element. The operation from then on is like any other automatic kettle. Read the rest of this entry »
Three main types of domestic, free-standing, portable electric heaters are widely used: radiant, convector and fan heaters. Some appliances combine different heater types, such as a convector plus a radiant bar.
Heat is produced by an element that glows red-hot when power is supplied to it. The heat generated by this action is directed by a highly polished reflector through an open front protected by a metal grill. The element can be externally wound on a ceramic mount or internally mounted in a heat-resistant silica glass tube. Simple switching of the element/s is included and faults can easily be traced. Read the rest of this entry »