Do you really need an outdoor filter?
What does PoE do?
PoE, or also known as outdoor filter is heavily promoted by most filter companies out there. However, does PoE really make sense in every single case? Let’s take a look.
First of all, it is important to understand that PoE is in 99% a sediment filter. It is able to remove suspended particles: rust, dust, sand, stones, clay, etc etc. It does not remove chlorine, chemicals, heavy metals. Some sand filters claim to remove chlorine, which is not a good thing, since your water is usually stored in water tank, and without chlorine microorganisms will grow there a lot faster.
all about expectations
Since PoE removes all these suspended particles, why not just install it? There is a catch though, it will be removing everything that is coming into your system. But what about everything that is already inside your system? If your house is relatively old, your pipes and tank could be covered with rust inside. No PoE, no matter the claims, can magically clean your whole water system. And even long rinsing will not get all, or even significant portion of dirt inside your system out in one shot.
At this point, you may be seeing some occasional dirt and wondering “how come I did invest into this expensive PoE and it does not protect me”? And then comes a water shutdown…
There will be a lot of disturbance inside the system when water returns after a shutdown. Water filtered by PoE rushes down the pipes, picking up the dirt that settled there, into the tank, picking up more dirt or rust from the very bottom and delivers all that through your tap.
It will take few hours to rinse all this “disturbed” dirt to acceptable levels. This is why so many people experience dirty water, even with finest PoEs installed, right after water shutdown. But there is another aspect to it, the water is not only dirty with visible particles, but also has this yellow/brownish color. And this is… also normal and expected.
Unlike rust, which is form of solid iron, dissolved iron is invisible and no PoE to our knowledge is able to remove it. Removing dissolved iron in large quantities is complicated and requires an oxidizing agent, in other words a chemical that needs to be refilled. If any PoE manufacturer claims that their system is able to remove dissolved iron without any use of chemicals, you can ask them by what process it happens.
Anyway, iron is required for our body to function, there is nothing wrong in having some dissolved iron and, in addition, quality PoU is usually able to remove it. However, when it oxidizes, it turns into rust (bite an apple and leave it on the table for 20 minutes, it turns brown, which is exactly that process of oxidized iron). So when there is water shutdown, or when you do not use water for long time, more air than usual enters the system and stays there for longer time. Oxidizing dissolved iron leads to… brownish/yellowish water. Once again, it normalizes after few minutes or hours, but once again – PoE cannot prevent that.
So yes or no to PoE?
In our professional opinion, PoE can be useful, but you must have the right expectations when getting it. PoE is not a magical tool that will clean your pipe/tank system, it does not replace PoU, it does not remove what it is not designed to remove. We recommend PoE in 2 cases:
- Your house is new, with new pipes and tanks. In that case, PoE will help keeping pipes and tank in clean condition
- Your incoming water is extremely bad and PoE, even with limitations described above, will be helpful (say you have stones or sand coming though and main goal of PoE is protecting you from sediment)
In other cases, PoE can be helpful, but not necessarily required, and it is much more important to invest into good PoU and probably local pre-filters for shower and washing machine, in case your system is already too rusty/dirty. When enemy is already inside (dirt inside your system), there is no reason to cut off the entrance anymore, don’t let it exit!