In terms of material, we can divide the pre-filter into filter element, filter element and pipe. The filter elements are all plastic. When buying, you should be optimistic about the thickness, not less than 4mm. The filter element is generally made of stainless steel, mostly 316 stainless steel, we have no choice. Most of these pipes are made of copper.
But copper and copper are also different, red copper, brass, imported copper (I still don't know what imported copper is, I haven't bought it anyway). For household use, the flow rate is not large, and the brass flow rate is sufficient.
Accuracy is very important, or a parameter of the pre-filter. The higher the accuracy, the cleaner the filtered water. But the accuracy is too high, it will affect the water pressure-think about the end of the water purifier in our house, the accuracy is quite high, but the amount of water is not as large as pee.
It is recommended to choose products with an accuracy of 40~80μm. This series is also the mainstream of the market.
In terms of functionality, it is not recommended to make it too complicated. Both the LCD screen and the water pressure gauge will be displayed after the actual installation. When the filter is cleaned throughout the year, it will not move except for one accident.
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