# Qwen — raw output, 2026-09-14 09:19 (+07), free, Qwen3.7-Plus, "Авто" mode (thinking and search, "+40" sources), one message, no follow-ups Interface Russian; answer in English. Copied with the reply's copy button; `[[n]]` are citation chips. Chat URL kept open for review. --- Fixing a dripping single-lever mixer tap is one of the most rewarding and straightforward DIY plumbing tasks. After about 10 years, the internal **ceramic cartridge** (the part that controls water flow and temperature) naturally wears out, causing the drip. Here is your complete, beginner-friendly guide tailored for Portugal. --- ### 🛠️ 1. Tools You Will Need You likely have most of these at home. If not, they are inexpensive and available at any Portuguese hardware store (*loja de bricolagem* or *ferraria*): * **Chave Allen** (Allen/hex key) – Usually 2.5mm or 3mm. * **Chave de fendas** (Screwdriver) – Flathead (*plana*) or Phillips (*estrela*), depending on your tap. * **Chave inglesa** (Adjustable wrench) – To undo the retaining nut. * **Alicate** (Pliers) – Optional, but helpful for stubborn parts. * **Pano ou toalha velha** (Old cloth/towel) – To protect the basin and plug the drain. * **WD-40 or a descaling spray** (*produto desincrustante*) – Very useful in Portugal due to hard water/limescale buildup. --- ### 🛒 2. What to Buy (and What to Ask For) **Do not buy the replacement part before opening the tap.** Cartridges look similar but vary in diameter (usually **35mm or 40mm** in Portugal [[33]], [[35]]) and have different pin configurations on the bottom. If you buy the wrong one, it will not seal or fit. **What to do:** 1. Disassemble the tap first (Steps 1–5 below). 2. Take the old cartridge out and bring it to the store with you. 3. **What to ask for:** *"Olá, preciso de um cartucho cerâmico de substituição para uma torneira misturadora de lavatório. Pode ajudar-me a encontrar um com o mesmo diâmetro e encaixe?"* (Hello, I need a replacement ceramic cartridge for a basin mixer tap. Can you help me find one with the same diameter and fitting?) **Other items to pick up while there:** * **Massa de silicone para torneiras** (Plumber’s grease) – To lubricate the new cartridge’s rubber seals. * **Fita de PTFE** (Teflon tape) – Good to have on hand, though often not strictly needed for just a cartridge swap. --- ### 📝 3. Step-by-Step Instructions **Step 1: Shut off the water supply** Look under the basin for two small isolation valves (*torneiras de corte*). Turn them clockwise (to the right) until tight. If your sink doesn’t have these, you must turn off the main water supply (*torneira geral*) for the house. Turn the dripping tap on briefly to release pressure and confirm the water is off. **Step 2: Protect the basin and plug the drain** Place a towel over the basin surface to prevent scratches. **Crucial:** Put the plug in or cover the drain with a cloth. Dropping a tiny screw down the drain is the most common DIY disaster. **Step 3: Remove the lever handle** Look for a small plastic cap on the handle (often marked with red/blue dots for hot/cold). Pry it off gently with a flathead screwdriver. Underneath, you’ll find a small grub screw (*parafuso prisioneiro*). Use the Allen key to loosen it (you don’t need to remove it completely, just enough to free the handle). Pull the handle straight up and off. **Step 4: Remove the decorative cover and retaining nut** You will now see a dome-shaped decorative cover (*capa decorativa*). Unscrew it counter-clockwise by hand. If it’s stuck due to limescale, apply a little WD-40, wait 10 minutes, wrap it in a cloth, and gently use pliers. Underneath is a brass retaining nut (*porca de fixação*). Use the adjustable wrench to loosen and remove this nut. **Step 5: Remove the old cartridge** Pull the old ceramic cartridge straight up and out. Note its orientation (which way the two small alignment pins on the bottom face). Inspect the inside of the tap body. If there is limescale or debris, clean it gently with a cloth and a bit of vinegar or descaling spray. **Step 6: Install the new cartridge** Apply a thin layer of plumber’s grease to the rubber seals on the bottom of the **new** cartridge. Insert it into the tap body, ensuring the alignment pins fit perfectly into the corresponding slots in the tap body. It should sit completely flush and not wobble. **Step 7: Reassemble** Screw the brass retaining nut back on. Tighten it firmly with the wrench, but **do not overtighten**, as this can crack the ceramic cartridge or strip the threads. Screw the decorative cover back on by hand. Place the lever handle back on, align it correctly, and tighten the grub screw with the Allen key. Pop the plastic hot/cold cap back into place. **Step 8: Test** Turn the water supply back on slowly. Turn the tap on and check for smooth operation. Turn it off and observe for a few minutes. No drips? Congratulations, you’ve fixed it! --- ### 🚩 4. When to Stop and Call a Plumber (*Canalizador*) Know your limits. Stop and call a professional if: 1. **The retaining nut is completely seized:** If it won’t budge even after applying penetrating oil and using proper tools, forcing it can crack the entire brass body of the tap. A cracked tap body means the whole tap must be replaced, which involves disconnecting pipes under the sink. 2. **The tap body is cracked or corroded:** If you see visible cracks or heavy corrosion inside the tap housing, a new cartridge will not seal properly. 3. **It still drips after replacement:** If you installed the correct cartridge perfectly and it still drips, the internal valve seat of the tap may be damaged. 4. **Water leaks from the base:** If water pools around the base of the tap when turned on, the main O-rings or internal seals of the tap body are compromised. 5. **You feel unsafe or unsure:** If you cannot find the isolation valves, the main house valve is stuck and looks like it might snap, or you simply feel out of your depth, there is no shame in calling a *canalizador*. It is cheaper to pay for an hour of a plumber’s time than to flood your bathroom or buy a whole new tap. ### 🇵🇹 Quick Portuguese Hardware Store Cheat Sheet * **Single-lever mixer tap:** *Torneira misturadora monocomando* * **Basin:** *Lavatório* * **Cartridge:** *Cartucho (cerâmico)* * **Adjustable wrench:** *Chave inglesa* * **Allen key:** *Chave Allen* * **Plumber’s grease:** *Massa de silicone* or *Graxa para torneiras* * **Plumber:** *Canalizador* Take your time, work methodically, and remember: the most important step is taking the old cartridge to the shop to guarantee a perfect match! --- First read: all six steps in order across eight numbered steps, the plug-the-drain warning, 35/40 mm, a full Portuguese cheat sheet (parafuso prisioneiro, porca de fixação, capa decorativa, canalizador). "Torneira geral" for the stopcock is understandable (the usual term is "torneira de segurança" or "registo geral"); "ferraria" again for the shop. Five-point stop list including "you feel unsafe". Checks in the sheet.