Water Filter Installation in Taipei: The System We Install, What It Costs and How to Maintain It

Why we install water filters

Most foreigners we meet in Taipei get their drinking water the same way: two big bottles from the convenience store, every few days, carried home by hand.

Taiwan's tap water is treated to drinking standards at the plant, but most apartments store it in a rooftop tank and send it through the building's own pipes, some of them decades old. That's why very few Taiwanese households drink straight from the kitchen tap. Most of them boil it or filter it.

A simple under-sink filter is the everyday Taiwanese solution. It sits in the cabinet under your sink, connects to the cold water line, and gives you filtered water from its own small faucet. It's the system we recommend, and the one we install for our clients.

The system we install

We use a Taiwan-made 5-stage filter system (BSMI registration model: AS-W105). It arrives fully assembled, with all five filter housings, tubes and connectors already joined, so installation is clean and quick.

• Size: 42 cm wide, 15 cm deep, 45 cm tall. It fits in a standard kitchen sink cabinet.
• Made in: Taiwan. Filter housings, connectors and tubing are made by a Taiwanese manufacturer and meet food safety requirements.
• Filters out: sediment, rust, chlorine, trihalomethanes (chlorine by-products such as chloroform), organic contaminants, pesticides, and unpleasant tastes and odors.
• Included parts: 4 m of 1/4 inch tubing, a filter housing wrench, the faucet connector, a 1/4 inch shut-off valve and a wall mounting bracket, plus the warranty card and installation guide.

What each of the five stages does

Stage 1: 5 micron PP sediment filter (NSF/SGS certified, made in Taiwan)

Catches sand, rust, hair and other larger particles. It protects the stages after it, so it's the one that gets dirty fastest. Replace about every 3 months.

Stage 2: UDF granular coconut shell activated carbon (SGS certified, made in Taiwan)

Removes chlorine, trihalomethanes, organic contaminants, pesticides, and odd colors and smells. Carbon becomes less effective the more water passes through it. Replace about every 6 months.

Stage 3: CTO coconut shell carbon block, 5 micron (NSF/SGS certified, made in Taiwan)

A compressed carbon block that does the same job as stage 2, more thoroughly. The whole cartridge is NSF/SGS certified. Replace about every 6 months.

Stage 4: K-5633 softening resin (SGS certified, made in Taiwan, using NSF certified resin imported from the UK)

Softens the water by capturing limescale, the white residue you see in kettles. How long it lasts depends on how much water you use and how hard your local water is. When you notice more tea stains or scale again, it's time to replace it.

Stage 5: T-33 post carbon filter (NSF/SGS certified, made in Taiwan)

A final polish that improves taste and removes any remaining odor. Replace about every 6 months.

A note on the softening resin. Softening resin swaps the calcium in the water for a small amount of sodium, and it can change the taste slightly. If anyone in your home is on a low-sodium diet, has heart or kidney conditions, or if you're preparing water for a baby, tell us before installation. Low-sodium and sodium-free resin options are available. Sodium-free resin has a slightly sour taste.

What it costs

We quote each home individually, based on the filter model and how the installation works in your kitchen (sink cabinet space, water line access, whether the landlord wants a specific setup). You get a clear quote before anything is installed.

Installation includes a consultation to check your kitchen, explaining the installation to your landlord in Chinese and getting their approval, a professional installation, and a test run with you before we leave.

Replacement filters. A full set of replacement cartridges costs around NT$565 at the time of writing. Most households replace the carbon filters about twice a year, plus the sediment filter every 3 months, so expect to spend roughly NT$1,500 a year on filters.

Filtered water vs. bottled water

Here's a simple comparison for one person who buys two large bottles of water every three days. A large bottle at a convenience store usually costs around NT$20 to NT$40.

• Bottled water: about NT$5,000 to NT$10,000 a year
• Filter, first year: a one-off system and installation cost (quoted by model and setup), plus filters
• Filter, every year after that: about NT$1,500

So for one person, the filter usually pays for itself within a few months. For a couple or a family, or if you also use bottled water for cooking and coffee, it pays off even faster.

And that's only the money. You also stop carrying heavy bottles home, stop running out late at night, and stop sorting a pile of plastic bottles for recycling day.

Who it's for

It's a good fit if you:

• Plan to stay in your apartment for a year or more
• Live with a partner or family, or cook at home a lot
• Live in a walk-up building and are tired of carrying water up the stairs
• Drink a lot of tea or coffee and want water without chlorine taste or limescale

It's probably not worth it if you:

• Are only staying a few months. For a short stay, bottled water is cheaper.
• Rent from a landlord who won't allow any changes to the plumbing. In that case a countertop dispenser you refill by hand is the better choice.

How to maintain it

A filter is only as good as its cartridges. An old, overdue filter can do more harm than good, so this part matters.

1. Follow the replacement schedule. Sediment filter about every 3 months. Carbon filters (stages 2, 3 and 5) about every 6 months. The softening resin when tea stains or scale come back. Heavy use or poor water quality means replacing sooner.

2. Flush new filters. After installing a new carbon filter, let the water run for 3 to 5 minutes before drinking. Black specks in the first water are harmless carbon dust and normal.

3. Store spare filters properly. Keep unused cartridges sealed in a cool, dry place. Use spare resin cartridges within about a year.

4. Watch for warning signs. Slower flow usually means the sediment filter is clogged. A chlorine taste or smell coming back means the carbon filters are due.

5. Replace it yourself or let us do it. The filter wrench is included and swapping a cartridge takes a few minutes. If you'd rather not, we'll remind you when your filters are due and replace them for you.

Get it installed

If you're tired of the convenience store water run, send us a message about our water filter installation service. Tell us roughly how big your kitchen is and whether you're renting, and we'll take it from there, including the conversation with your landlord.

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