Reduce the temperature in the hot water tank

Reducing the temperature in your hot water tank by 5 ºC can save you EUR 80 per year.

Choose the correct temperature, and save money
If the temperature in your hot water heater is set at 60 ºC, you can easily reduce the temperature by 5 ºC and thus save EUR 80 per year into the bargain.

The optimal temperature in a hot water cylinder is 55 ºC, which is warm enough for a proper bath or shower, and for removing grease and dirt. If the temperature is higher, more limescale is produced and this can have a bearing on the life of the tank. If the water temperature is lower than this, there’s an increased risk of bacteria growth in the water, so the temperature should not be less than 50 ºC at the tap.

Avoid bacteria growth
Legionella and other bacterial growth can only survive if the temperature in the hot water tank remains constant over an extended period of time. This is why you should let the water flow free a little to induce a change in the temperature. This applies especially if you have been away and may have switched off the hot water tank completely.

Hot water tanks should not be too large
The risk of bacteria growth is minimised by making sure that your hot water tank is not too large. A hot water cylinder of 60-110 litres is sufficient for the average household. The cylinder should be insulated with at least 50 mm of foam insulation.

Where is the hot water tank located?
It’s possible to have one or more hot water tanks in the house; but normally there will be only one, located in the utility room with the hot water piped to the kitchen and bathroom.
 
Save water with aerators and water limiters
A water saving shower head uses 6-10 litres of water per minute compared with an ordinary shower head, which uses 10-20 litres per minute. Aerators mix water with air to make the jet more powerful than it actually is. Water limiters reduce the water flow rate so you use less. You can save up to 40% of your hot water by combining an aerator and a water limiter.

Page last updated 17.12.2009