How to Anti-freeze for the Differential Pressure Switches in winter?

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If the air temperature is too low to a certain extent, the liquid in the pressure tap may freeze. Once the frozen volume expands, it will squeeze the sensor and cause damage, affecting the measurement. The maintenance method of the Differential Pressure Switches needs to be divided into different seasons, because the temperature in each season is different, the protective preparations need to be done are also different, especially in the northern region, the outdoor temperature in winter is lower than - 10 C, because the water in the two copper pipes, which connected with the heat exchanger by the differential pressure type flow switch, does not flow, when the air-cooled heat pump unit is in the standby state, if the Differential Pressure Switches is connected with the copper pipe and the copper shell, if no insulation of Anti-freezing will be done, It may freeze the pipe of Differential Pressure Switches.

To solve this problem, we suggest that the connecting copper pipe from heat exchanger to Differential Pressure Switches should be as short as possible. The connecting copper pipe and copper shell should be wound with electric heating wire. The electric heating wire is 10W ~ 15W / m. The material of electric heating wire is similar to that of compressor crankcase heater in the same shape. The electric heating wire can also be covered with insulating heat shrinkable pipe to increase the electrical reliability.

GE-511A Differential Pressure Switches with copper pipe to detect the pressure

If no anti-freezing for the small copper pipe, it will freeze in the winter

After the electric heating wire is wrapped, the connecting copper pipe and copper shell shall be insulated outside. The insulation thickness is better than 10 mm, and all the insulation boards are better pasted without omission. After such treatment, the electric heating line and crankcase heating belt shall be connected in parallel, and attention shall be paid to that the power supply voltage shall be consistent, that is, the electric heating line only works when it is in standby mode. For the high demand, an output can be added to the control board to start the electric heating line when the outdoor temperature or water temperature is lower than 2 C, or the electric heating line can be controlled by a temperature controller.

[ The Differential Pressure Switches in the automatic Backwash Filter system ]

If no anti-freezing for the small copper pipe, it will freeze in the winter

A flow switch is a device that monitors the flow of air, steam or liquid. It sends a "trip signal" to a different device in the system, such as a pump. The Differential Pressure type Flow Switches is to control the system according to the differential Pressure, which made by the water flow . Set the upper or lower limit for the Flow Switches. When the flow reaches the limit value, the Flow Switches will send a signal or alarm, and the system will run or stop. Generally, the system requiring flow will use a Flow Switches. According to the different system, the type of Flow Switches and other factors, the place of use is also different, which should be determined according to the specific situation.