Welcome to A2Ks Immersion Page

Immersion

Immersion heaters provide a handy direct source of heat from electricity which fail from tile to time bringing electricity in direct contact with water and people through the hot tap pipework leading to possible “shock”. There are a few types and sizes of heaters, 2kW, 3kW, 12”, 14”, 18”, 27” which only take between 8.7A and 13A depending on the kW.

Isolating

Switches 20A double pole are too often overheat due to poor connections developed over time inside the switch causing resistance in the back of the switch generating heat due to the power being developed, I^2x R in the bad connections. The heat then increases over time to the point of melting and burning the switch enclosure leading to possible localised fires and further to large room and building fires.

Damaged

To the switch enclosure due to the overheating of the contacts can be detected if the metal facier plates become hot to touch this should not be ignored, plastic switched may be discolored round the switch. A qualified electrician should be called in to investigate the possible problem. Switches with large integrated lights are slightly warm to touch anyway not to be confused with blatant hot to touch.

Wires

Behind the switch harden due to the overheating become brittle, their insulation becomes hard and disintegrates leaving the conductors exposed possible direct contact with their surroundings leading to a possible “shock” situation.

Bang

Goes the heater element inside the tank and hopefully the trip and or the RCD too disconnecting the supply to the heater preventing the possibility of shock through the hot water pipework

MCB

Miniature Circuit Breakers for overload in a circuit to protect the cable to the appliance. They come in a few flavors type A, B, C and can distinguish between a short and just a spike. Type B is the straight domestic type without delayed action and to meet the cable current carrying capacity of 2.5mm^2on a single run is 20A maximum and to protect both the cable and a 3kW immersion a 16A MCB is best suited.

RCD

The lifesaver relies on a 30/80mA Neutral/Earth short to operate and disconnecting the supply from the appliance. They are found as an integral part if appliances electric lawnmower plugs, in extension lead and as a plug to be wired to an appliance. They are also in the consumer unit covering power ring sockets, bathroom, kitchens and the garden socket outlets.