How to change a faucet seal ? Which gasket to choose ?

A small faucet leak can end up being very expensive. Too bad, because it is not very complicated to repair it: most of the time, there is only one seal to change. To change a faucet seal, you don’t need to be an experienced handyman; just follow a few very simple steps. And choose the right joint.

My faucet is leaking; it’s serious ?

A leak will always get worse. If we don’t repair, little drop by drop will become big.

An expensive waste

Is it reasonable to leak so much water? A very small tap leak represents a flow rate of half a liter per hour. Which is already more than 4000 liters per year! About 17 euros wasted… provided it’s a very small leak.

Find the cause of the leak

A leaking faucet is usually related to seal wear. Very often it is caused by over-tightening the tap. The seal does not withstand pressure variations and ends up no longer providing a seal. This can also come from the natural wear of the seal, linked to its aging. A leak is an opportunity to check the condition of the O-rings and valve seals, and if necessary to change them. If the faucet seal has lost its flexibility, is stiff and cracked, it’s time to replace it with a new one.

Mixer or mixer?

The wear of a seal is often the cause of a leaking mixer tap. Especially if it’s old. But in the case of a mixer, it would rather be a cartridge problem (which will have to be changed). We tend to tighten a leaky mixer tap more tightly… This stops the leak for the moment, but contributes to accelerating the wear of the seal. Sooner or later you have to change the seal.

Changing a seal: easy and inexpensive

Why let this repair drag on? As you will see, it is not very complicated. Especially since changing a faucet seal will not cost you much. Barely five euros. It is not essential to call a plumber. You probably already have the necessary tools, and gaskets are easily found in stores.

How to change a gasket in 7 steps

With a little method, your seal change shouldn’t be a problem. You have it for half an hour maximum – half as much if you are a good handyman.

Start by preparing your tools

  • You need two screwdrivers: a thin-bladed flat and a Phillips.
  • Also provide an adjustable wrench (or pliers).
  • For a mixer, you will need an Allen key (3 mm) and a 22 mm box spanner.
  • You will also need: silicone grease (compatible with drinking water), a new gasket, a tape measure (or a caliper) and a cloth.
  • The joints toric are removed from their location using the tip of the screwdriver. If they don’t need to be changed, you can grease them.
  • To remove the valve sealpry with the tip of the screwdriver.
  • Install new O-rings and screw tight.
  • Before installing a new valve seal, clean its location. After installing it, grease it. You can put the faucet head back in place. With the spanner, reinforce the tightening.
  • The O-ring owes its name to its torus, ring shape. It is classified according to the DIN/ISO 1629 standard. The most common O-rings are made of nitrile NBR (Nitrile Butadière Rubber). These seals are valued for their heat resistance and compatibility with silicone petroleum based fluids. They have three levels of hardness, measured 70, 80 or 90 shores. Their diameter ranges from 3 mm to 22 mm (inner diameter). Whatever their size, it must correspond exactly to its location. If necessary, measure the inside dimension and the width of the cavity. The exact size of the gasket can be obtained by measuring with a vernier caliper.
  • The valve gasket seals the closure of a flap valve. He can be plein or perforated, depending on the faucet or mixer model. Made of EPDM, an elastomer made ofEthylene, PropylisNo, Godene and Monomtime, a valve seal is able to withstand a maximum temperature of 110° C. But over time, the opening and closing movement of the valve ends up wearing down the polymer. When the time has come to replace it, note its dimensions and check whether it is drilled or not.

Turn off the water and drain the tap

Before any intervention, it is essential to cut off the water supply to the leaking tap. Either by closing the shut-off valve, if there is one, or by directly shutting off the main valve of the accommodation. When this is done, bleed the circuit by opening the valve whose seal you need to change. Don’t forget the toilet bowl, if you don’t want to mop the floor!

Dismantle the faucet

First you need to disassemble the handle tap, starting with the cover. Use the channel pliers to remove the cover. Then remove the fixing screw with a thin-bladed screwdriver. You can then dismantle the handle.

When it’s done, you still have to dismantle the head tap. Use your adjustable wrench or pliers for this. Remove the nut securing the faucet head. If necessary, especially in case of rust, apply a coat of penetrating oil. Unscrew the head to be able to check the condition of the seals. As the mixer tap has two heads, for hot and cold water, check the condition of all seals. You might as well change those that are beginning to show signs of wear, this will prevent future leaks.

Remove worn seals

With the faucet head unscrewed, you see the O-rings, located on the mechanism. A valve seal is located at the base. It provides sealing.

Install new seals

Replace old gaskets with new ones. But first, check the status of the installation.

NB : There are so many seal diameters that you may hesitate when buying a new one. Measure your joint precisely, using a tape measure or a caliper. If in doubt, the easiest way is to take the old joint to the store to buy the exact same one.

Reassemble the faucet and check for leaks

When everything is reassembled, you still have one last check. Re-open the water supply to check that the repair is watertight. Does the leak persist? Repeat the operation, and this time make sure to tighten the valve heads tightly. If the faucet is still dripping, you probably need to add silicone grease to the valve seal and on the thread.

And if the leak still persists, it is because the seal is not the only cause. If the faucet handle leaks, you can remove it and wrap the threads of the head with a roll of Teflon, before reassembling it. In the worst case, you have only one solution: replace your old faucet.

For a mixer tap, change the cartridge

The mixer tap does not have two heads, but a single control for hot and cold water. The procedure is a little different, since it will be necessary to change the mixer cartridge, inside which the seals are located. To do this, remove the pad located under the lever (the control) to access the cartridge. Use an Allen key to unscrew the control fixing. Then a pipe wrench to unlock the cartridge holder. Then remove the cartridge from its slot. Replace it with the same model. Reassemble and test for leaks.

How to choose the right faucet gasket?

Make no mistake in choosing the replacement gasket. You need to choose the right diameter, thickness and material. In the large family of seals, those intended for valves are the joints dynamic, designed to withstand repeated movements. As for seals static, they are made to be compressed. This is the case for vulcanized fiber seals, EDPM rubber seals, valve seals (drilled or not) and O-rings (both dynamic and static).

In faucets, you will need O-rings and valve seals.

To be prepared for any eventuality, you can keep a stock of seals at home. But be sure to store them in good conditions. Otherwise, they risk being worn out before they can be used! Keep your faucet seals away from heat, dust and chemical attack.

Leave a Comment