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Filtered Water Tap – Installing a Filtered Water Tap

Several manufacturers produce specially designed filtered water units which can be mounted in the cupboard under the sink to provide filtered water. There are two options to consider – the filtered water may be supplied via a separate worktop mounted tap or, a combination mixer tap may be fitted which has hot, cold, and filtered water. The later is often more convenient as no additional space is required on the worktop and many people prefer the convenience of a single tap.

You should check that your water pressure meets the minimum / maximum pressures stated in the instruction manual. If necessary, a pressure reducing valve may be fitted.

Fitting a new triple outlet tap obviously requires a little more work as you will need to replace the existing tap assembly with the new type. Whichever type you choose, you will need to examine the contents of the kit and read through the installation instructions carefully.

All in One Water Tap

Examine the contents of your new filtered water kit. This will contain the new triple outlet tap, flexible pipe tails, mounting bracket for the tap, filter unit and mounting bracket, and flexible water hoses to supply the filtered water. There may be additional items such as a small electronic device which will indicate when the filter needs changing.

Mounting the Filter Unit

Mount the new filtered water unit inside the under sink cupboard ensuring that it is securely held in its bracket and, that the position allows easy connection to the plumbing. The installation leaflet will give suitable details about maximum distances. Units can often be mounted horizontally instead of vertically which makes it easier to find a suitable position without the cupboard shelves having to be moved or modified.

Connecting the Plumbing & Mounting the Tap

Switch off the hot and cold water supply to the sink. Ideally there will be service / isolating valves on both of these allowing you to isolate them easily. If not, you should switch off the main supply valves for hot and cold water, drain down the pipe work, and fit suitable double check service valves before proceeding.

Make sure that the flexible pipe tails supplied with the new tap will comfortably reach the existing water supply connections. If this is a new installation, or the position is unsuitable, you will have to modify the pipe work to suit.

With the service valves switched off, disconnect the existing mixer tap hot and cold flexible tails from the supply pipes and remove the tap from the sink or worktop.

Details will vary between makes, but the next job will usually be to connect the new flexible pipe tails to the base of the tap and the small diameter plastic pipes which go to the filter unit and back. Place the upper mounting gasket on the base of the tap assembly and position in the tap hole. Fix in position using the horseshoe plate and stud together with any underside mounting washers

If fitting to the worktop rather than the sink unit, hopefully the tap hole in the worktop will be the same size as that required for the new tap. If not, or if this is a new installation, you will need to cut the appropriate size hole in the worktop. Check carefully that this will not clash with anything underneath and drill from above to avoid splintering the worktop.

Connect the new flexible pipe tails to the hot and cold water supply connections. Make sure you have these the right way round. Generally the hot is on the left and the cold on the right but this isn’t always the case.

Connect the plastic water hoses to and from the filter unit as per the installation leaflet.

Open the isolation valves and thoroughly inspect your work. Open the filtered water tap and allow to run for a minute or so to flush it through. Repeat for the hot and cold taps.

Separate Filtered Water Tap

These kits often come with a self piercing clamp type valve allowing connection to the existing cold water pipe under the sink without the need to switch off the water supply or modify the existing pipe work. The simplicity of these makes them a popular choice for DIY installation.

Carefully assess where you wish to fit the new tap so that it overhangs the sink bowl correctly and that there is enough room on the worktop. You will also need to ensure that you can access the underside during installation and that there are no other pipes or services in the way.

Mounting the Filter Unit

Having done this, decide where you are going to mount the filter unit – these can often be mounted horizontally instead of vertically which makes it easier to find a suitable position without the cupboard shelves being in the way. Ensure that the unit is close enough to the cold water supply to the sink, and to the new tap position, for the flexible pipes to and from the filtered water unit.

Connecting the Plumbing & Mounting the Tap

Carefully cut the required size hole in the worktop. Details for this will be included with your kit. Cutting from the top downwards will create a neater hole and prevent splintering of the worktop surface. As mentioned earlier, check carefully below the drilling point to ensure there is nothing in the way beneath.

Mount the filter unit inside the cupboard using the supplied bracket. Connect the flexible water pipes to the tap and the saddle valve as per the manufacturer’s instructions. You will now be ready to connect to the water supply. Place the G clamp type saddle valve over the cold water pipe and fasten in position. This should be tight enough to prevent it moving but don’t over tighten as you may distort the pipe. Double check this is indeed the cold water. Turn the ‘tap head’ of the valve to pierce the pipe, and tighten. The valve is now ready to supply water but will be in the closed position. Making sure that everything is connected up correctly first, open the saddle valve and inspect your work to ensure no leaks. Finally, open the new filtered water tap and allow the water to run for at least a minute to flush the work through.

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