After moving to a developing country, one of my biggest concerns is the water quality. Most diseases here are caused by poor water and sanitation conditions, therefore, it is recommended to boil water before drinking. However, boiling can just remove pathogenic bacteria and virus, we won’t be able to get rid of turbidity or chemical pollution.
Therefore, I decided to buy an RO water purifier, the A.O. Smith AR75-A-S-2. As this is my first full-fledged water purifying system, I really hope it is not a scam. Let’s see if it can improve the water quality in my house.
Design & Features
The A.O. Smith has an under-sink design, that means the whole purifier can be hidden in your kitchen cabinet. There is only a faucet on the sink so that we can easily get clean water. The installation process is not complicated but you will need to follow the instructions carefully. Basically, you will just need to connect the filters, connect the system to a water source, connect the outlet to a water drain line, install the faucet, and you’re all set. Make sure to clean the carbon filter and dispose at least 10 liters from the water storage tank. The tank has 9.46 liters of storage capacity.
The AR75-A-S-2 purifier features a 5-stage filtration system. It includes a 5 μm sediment filter, a Pre GAC filter, an 1 μm sediment filter, a side stream flow-type RO membrane, and a composite GAC & mineral filter.
The best feature of the purifier is, of course, the side stream RO membrane filter with an increased purified water recovery rate. The clean/waste ratio of the system is 1:1 while that of other purifiers is just 1:2 or even 1:3. That means for every liter of clean water produced, the system dumps just 1 liter of waste water. Besides, the lifetime of the RO membrane is also increased by 1.5 times. So, you won’t need to replace the RO filter in up to 3 years.
The RO filter will also remove hard water contaminants like arsenic, lead, copper, barium, chromium, mercury, sodium, nitrite, nitrate, or selenium.
Another nice feature of the A.O. Smith is the electronic monitoring system with RO filter replacement reminder. We have a LED display showing the working status, water source, water tank, RO Side Stream membrane and other filters’ condition. You might not see the display since the purifier is hidden in your cabinet, fortunately, you can also look at the light on the faucet. If it is green, everything is working fine. You only need to worry when the light turns orange or red; you will need to replace a filter then.
A.O. Smith suggested that the water coming out of their purifiers can be drunk directly and it’s better not to boil it. The last filter in the system improves the taste of water by removing organic impurities, therefore, the water doesn’t have a smell like tap water.
I didn’t carry out a full water test since it’s very costly and the manufacturer already gave me certified results. In my own experience, I’ve used the A.O. Smith purifier in the last 3 months and drink water directly from the faucet. I can feel that the water is significantly cleaner and fresher. Earlier when I boiled tap water, I was so worried when seeing white residue build up in my water kettle. It might be harmless but it looks terrible and the taste is also not as fresh as the purified water.
I used the Xiaomi Mi TDS pen to test the water quality. The pen can measure the amount of total dissolved solids, not biological contaminants. So we can check if the water contains any salt, metal or mineral. I made a comparison between the A.O. Smith purified water, the tap water, and the bottled water. The results didn’t surprise me.
The tap water is the hardest water with the ppm of around 180 while the purified water and bottled water have the ppm of less than 20. That means the purified water is quite similar to what you are drinking from bottled water like Aquafina or Dasani. Moreover, I feel like it tastes better, not as bland as the bottles.
- Clean setup
- Beautiful faucet
- Improved water quality
- Helpful LED display and faucet indicator
- Prolonged filters’ lifetime
The A.O. Smith AR75-A-S-2 is among the most expensive RO water purifiers on the market but it’s totally worth it. It costs me around $350 but I really love the efficient filters and some other high-end features. We at TechWalls highly recommend the product.
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