# A mesh filter at the house inlet: fitting and rinsing it yourself > Why a first-stage mesh filter matters, whether to choose a 50 or 90 µm mesh, how to fit the filter into the pipe and how to rinse it without a plumber. Web page: https://watertrade.com.ua/en/articles/article/setchatyj-filtr-ustanovka-promyvka · Other languages: [UA](https://watertrade.com.ua/articles/article/setchatyj-filtr-ustanovka-promyvka.md), [RU](https://watertrade.com.ua/ru/articles/article/setchatyj-filtr-ustanovka-promyvka.md) *November 5, 2026* ![Diagram: mesh filter with a clear bowl and two pressure gauges between ball valves, sand at the bottom and a drain valve over a bucket](https://watertrade.com.ua/uploads/articles/mesh-filter.jpg) Sand, scale flakes and rust from old pipes are the main enemies of everything downstream. They scratch the ceramic cartridges in mixers, clog aerators, settle in the water heater and ruin a fine cartridge within a month. A mesh filter catches this dirt first, and the mesh itself is not replaced — it is rinsed. ## What the diagram shows 1 — the mesh inside a clear bowl, 2 — pressure gauges before and after the filter, 3 — a drain valve for rinsing, 4 — ball valves so you can service the filter without shutting off the whole house. ## Which mesh to choose - **90–100 µm** — for sandy borehole water and as the first stage before other filters. It clogs slowly. - **50 µm** — when there is little sand but you want finer filtration, for example against rust from a building riser. - **Stainless steel mesh** lasts longer and cleans more easily. **Polyester** is cheaper but must not be scrubbed with a stiff brush. A mesh finer than 50 µm at the house inlet is usually overkill: it clogs quickly and eats into the pressure. Fine filtration is the job of cartridges in the next stage. ## Where to fit it 1. First at the inlet: in a house, after the pump and pressure tank; in a flat, straight after the main valve, before the meter and the pressure reducer. 2. Bowl pointing down, with the arrow on the body in the flow direction. 3. Leave 10–15 cm below the filter to unscrew the bowl, and room for a bucket under the drain valve. 4. A standard filter is for cold water only. Hot water needs a housing marked for hot water. ## Fitting it yourself 1. Shut off the water and release the pressure by opening the nearest tap. 2. Cut out a section of pipe and fit ball valves on both sides — you will use them every time you rinse the filter. 3. Seal the threads with hemp and paste or PTFE tape (see [“How to seal pipe threads”](https://watertrade.com.ua/en/articles/article/germetizaciya-rezby)). Mount the filter on the wall with a bracket so its weight does not hang on the pipes. 4. Slowly open the valve before the filter, bleed the air and check every joint for leaks. ## When and how to rinse it Watch the gauges: while the mesh is clean they read almost the same. When the difference reaches 0.5 bar or more, it is time to rinse. 1. **Quick rinse.** Put a bucket underneath and open the drain valve for a few seconds — the flow washes the dirt off the mesh. You can do this weekly. 2. **Full clean.** Close both ball valves, release the pressure through the drain valve and unscrew the bowl with the spanner. Rinse the mesh under running water with a soft brush. 3. Check the bowl’s O-ring: if it is flattened or cracked, replace it. Grease it with silicone grease and screw the bowl back by hand, without the spanner. > Never unscrew the bowl under pressure, and do not tighten it hard with a spanner — plastic threads crack. Mesh filters, housings and spanners are in [water filters](https://watertrade.com.ua/en/catalogue/filtry-dla-vody). What to fit after the mesh is explained in [“How to choose a water filter”](https://watertrade.com.ua/en/articles/article/kak-vybrat-filtr-dlya-vody). --- Watertrade · Phone: 067-421-96-27 · sale@watertrade.com.ua · Site map for language models: https://watertrade.com.ua/en/llms.txt