Working principle of domestic hot water circulation system

For domestic hot water circulation system, a set of check valves must be installed in advance when installing the backwater system. When the backwater system works, the cold water in the hot water pipeline will flow from the check valve to the cold water pipeline, and the water in the cold water pipeline will flow to the water heater, thus forming internal circulation and being heated by the water heater.

Because the hot water circulation system adopts temperature control, its temperature taking point can only be above the hot water return pipe (most manufacturers' temperature taking points are exposed to the water pipes below the return pipe system, which is inaccurate).

For example, the temperature in the main pipe (the set temperature of the water heater) is 42 degrees, and the set temperature of the circulation system is 33 degrees. When the main pipe uses water for a long time, the temperature in the main pipe is 42 degrees, and the temperature in return pipe decreases with time. When it is lower than the set value, the circulating system water pump restarts, causing unnecessary waste.

Taking a bath for a long time will increase the power consumption accordingly. The hot water circulation system adopts time and water flow control, and whether the circulating pump has return pipe can be effectively controlled.

Extended data:

Characteristics of domestic circulating water system;

First, manual control. Press the on/off key of the circulation system before use, and the system will work once until it reaches the set time or temperature, and the system will stop; If the water temperature gets cold in the middle of the shower, it needs to be restarted.

Advantages: simple operation, low manufacturing cost and relatively low price (installation with or without reflux pipe).

Disadvantages: In the process of use (such as turning off the water to wash your hair or applying shower gel for too long), the water temperature becomes cold, and hot water can only be available after restarting or putting down the cold water.

Second, temperature control. There are two ways to start: one is water flow start; One is remote start, and the working principle is the same: hot water loop needs to be reserved. There are also two kinds of systems: one is single temperature control, which works 24 hours after starting, which consumes a lot of gas and wastes the original intention of the system; The other is temperature plus time control, which is to ensure that the temperature in the hot water pipe is within the set value within the set time after starting.

Advantages: hot water can be guaranteed within the set time.

Disadvantages: only pipeline circulation can be carried out, with high use cost and large gas and electricity consumption. ?

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