Why can't you connect the filtration system directly to your existing faucet?

You've decided to invest in a filtration system or a reverse osmosis purifier to enjoy pure water right at home. You look at the freshly unpacked kit and notice a small, additional faucet. The first question that comes to mind is: "Can't I connect the filter hose directly to my main kitchen faucet, so I don't have to drill an extra hole?"

The short answer is NO, and the reasons relate to both hygiene and the technical functionality of the system. Here's why installing a dedicated faucet (or a special 3-way faucet) is strictly necessary.

1. The risk of recontamination: Hot water and residues
Your current kitchen faucet is designed to mix cold and hot water for household use. Unfiltered water — and especially hot water — constantly flows through the inside of the main spout and the aerator (the screen at the tip of the faucet).

Domestic hot water promotes limescale buildup and the development of bacterial biofilm inside the faucet. If you tried to pass filtered water through the same pipe that previously carried unpurified hot water, the filtration process would be instantly undone. The water would become recontaminated the very second it left the system, picking up bacteria and impurities from the inner walls of the old faucet.

2. The huge difference in flow rate (2 litres vs. 10 litres)
Classic filtration systems use thin 6 mm (1/4") hoses. These are designed to deliver a controlled flow rate of approximately 2 litres per minute, to ensure the necessary contact time between water and the filtration media (activated carbon, membrane, etc.).

Your kitchen faucet is designed for a much higher flow rate (approximately 8–12 litres per minute). If you connected the thin hose to such a large faucet:

• The pressure would be insufficient to fill the generous space of the large pipe.
• The water would flow "intermittently" or as an unsightly trickle.
• The aerator of the large faucet would not be able to function correctly at such a low flow rate, resulting in splashing or uncontrolled leaks.

3. Premature and costly filter wear
If you managed, through improvisation, to connect the system to the main faucet, you would end up using filtered water for everything: washing dishes, rinsing the sink, or washing your hands.

Filter cartridges have a limited capacity (e.g. 2000–4000 litres). By using ultra-filtered water for household chores, you will consume the filters' resources 5–10 times faster than normal. This turns a smart investment into a considerable and unnecessary monthly expense.

The right solutions for your kitchen
To benefit from pure water without compromise, there are only two professional options:

Option A: The small faucet (included in the kit)
This is the simplest method. It is installed in a corner of the sink or on the countertop. It has a very narrow internal channel, perfectly adapted to the 2 l/min flow rate, keeping filtered water completely separate from the raw water circuit. There are filter faucets available in different shapes and colours. Choose one that matches your kitchen.

Option B: The 3-way faucet (the premium solution)
If you don't want to drill an additional hole in the sink or prefer a minimalist design, the 3-way faucet is the ideal solution.

It completely replaces the old faucet and has two independent flow channels within the same body:

1. Channel 1: For hot and cold household water (standard connection).
2. Channel 2: A separate, isolated pipe through which only filtered water flows, operated by a separate handle.

This way, filtered water never comes into contact with unfiltered or hot water, maintaining its purity all the way to your glass, while the look of your kitchen remains modern and tidy.

Conclusion: Don't make compromises when it comes to your health. The filtration system needs its own dedicated path to you in order to do its job correctly.

Would you like to see our range of 3-way faucets available in various colours? Visit https://filtro.ro/baterii-cu-3-cai or contact us so we can help you choose the right solution.