Water Heating

Immersion heating is a way of providing hot water for a property. It works by fitting a heating element or elements to the inside of a water storage vessel like a cylinder and then filling with water and heating the water using an electrical supply to the element.

The electrical element is controlled by a thermostat that will switch it ‘on and ‘off should water temperature in the cylinder drop below 60°C. This temperature has been designed to help prevent the water from scalding the user. Leytonstone Plumbers can fit immersion heaters to cylinders. There is a cold water supply at the bottom of the cylinder that is controlled by a filling inlet valve. The heater can be made up of more than one heating element, depending on the size of the property and hot water demand. As soon as the water is at the correct temperature it is drawn from the top of the tank. If this heater is fitted in an unvented cylinder it requires a high limit thermostat which is set at 90°C so the water will not boil. There is a risk that something called legionella may form in this type of water heater. This is a great threat to human health. The legionella bacteria can form in water at a temperature below 60° centigrade, but will not survive for long at this temperature and dies if the temperature rises. Legionella survives at temperatures of between 20°C and 40°C and spreads itself in the form of a mist. As long as the water temperature is regulated it will not appear. A Leytonstone Plumber is highly aware of the dangers of legionella.

The legionella bacteria is better known as legionnaires disease and is still very rare and does not affect very many people each year, but the risk is still there.”