Circulator pump

A circulation pump is an electrically driven pump that continuously circulates the heated water in the drinking water pipes, and so provides immediately at each tap. Without circulation, the stationary hot water cools in the line, thus flows unscrewing the hot water tap first of cooled water before hot water comes. A circulation is especially important in widely distributed cable networks, where the distance between the hot water tank and tap has been designed for very large.

This is not only a comfort disadvantage to compensate for a circulation pump tries, but also a claim that arises from the Drinking Water Ordinance and the DVGW worksheet W551, with the aim to prevent legionella growth. Thus, large-scale systems, with more than 3 liters of water volume between the water heater and at least one sampling point, with a circulation line (or trace heating ) must be equipped. The circulation pump makes this back for the water transport through the loop and the circulation pipe for hot water generator.

In today's pumps there are different versions. In the ideal case, the circulation pump comprises:

• A temperature sensor at too low a return temperature ( variance comparison ) to activate the pump again " redeploy " the water.
• A check valve to prevent gravity circulation
• A timer that controls that only at certain times hot water is immediately zapfbar

Normally, the circulation pump does not work on its own. It is through a regulator (usually the heating controller) driven, which governs the entire system of water heating.

Benefits

When you open the hot water tap instant hot water comes ( in comfort ), also water is saved because there is no cold water running into the drain unused until warm water in the pipeline is up flowed.

Since the water can no longer stand in the pipe, the emergence of Legionella is largely prevented, but what a sufficiently high temperature of the back- flowing water provides. If this is not the case, the risk of legionella can through a circulation line increase.

Disadvantages

The high gas and oil prices make the circulation pump at a substantial cost factor, especially when the hot water pipes are not or only insufficiently insulated. The power consumption of the pump is taken into account.

With faulty hydraulic balancing of the system, incorrect design of the pump or pipes, defective insulation or other design errors, the temperature in the circulation line may drop to below 55 degrees Celsius. With warm water temperatures below 55 degrees Celsius there is a risk of colony formation of legionella.