The main reason is that the filter cartridge loses its antibacterial ability after long use, making the water purifier ineffective.

Do not connect the water outlet to the hot water pipe

In a water purifier, the water outlet must never be connected to a hot water pipe. Doing so can lead to serious consequences — the pipe may melt due to excessive heat and become damaged very quickly.

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Failing to replace the filter cartridges

Filter replacement must be done regularly to ensure the water remains rich in minerals and hygienically safe. If the filters are not replaced as recommended, using the filtered water can become dangerous.

The main reason is that over time, the cartridges lose their ability to eliminate bacteria, turning the water purifier into a useless device.

Moreover, during use, you should not attempt to repair or modify the purifier on your own when problems occur. Instead, contact professional technicians to ensure the purifier works efficiently, operates stably, and is installed correctly.

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Boiling filtered water before drinking

Many people believe that only boiled water is safe to drink, so they still boil filtered water before consumption. In reality, this is completely unnecessary.

The output water from a household water purifier has already been filtered to remove all impurities, dirt, heavy metals, and bacteria. It meets the Ministry of Health’s standards for direct drinking water, meaning you can drink it straight from the tap.

If the filtered water still contains beneficial minerals, boiling it can destroy those minerals, making the water less healthy than drinking it directly from the purifier. Additionally, boiled water must be stored properly and consumed immediately — otherwise, bacteria can contaminate it and cause illness.

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Choosing a purifier with more filters is not always better

A purifier with more filters does not necessarily mean better filtration. Normally, an effective water purifier has up to five filters, including:

• Three coarse filters,

• One RO (Reverse Osmosis) or Nano membrane, and

• One Cation filter (used in areas with high calcium or limestone content).

After passing through the RO or Nano membrane, the water becomes pure, but it also loses some beneficial minerals. Therefore, some purifiers are equipped with additional filters — 6th, 7th, 8th, 9th stages — to remineralize the water and add nutrients beneficial to the body.

Users should learn to distinguish between purification filters and mineral-replenishing filters in order to choose the most suitable and effective water purifier.