Alternate Water Ionizer Installation: Connect to Cold Water Line

Alternate Water Ionizer Installation: Connect to Cold Water Line

This guide illustrates Water Ionizer Authority’s recommended installation method for counter top water ionizers.  This installation method will make your counter top water ionizer easier to use, frees your faucet from adapters & hoses,  and protect it from damage that can be caused by accidentally running hot water through the unit.

Your water ionizer will still sit on the counter top near the sink, offering full access to the control panel.  The difference with this installation is how water is supplied to the unit.  Instead of adding an adapter to your faucet with the hose running from the faucet to your water ionizer, an adapter is placed directly in the cold water line below the sink.  This provides a constant supply of water to your ionizer which means no more turning the faucet on and diverting water to the ionizer.  The water supply has already been diverted below the sink using a dedicated water supply line for your counter top water ionizer.

Installation Parts & Requirements

This installation requires bringing a 1/4″ water supply line up from under the sink.  You will need to have a hole somewhere to bring the water supply line up above the counter for connection to your water ionizer.

Many customers opt to put a small hole in their counter top behind where they plan to place their water ionizer so that it can’t be seen.  Others will remove a side sprayer or soap dispenser and bring the line up through that hole.  Others with stainless steel sinks will opt to put a 1/4″ hole in the sink near their existing faucet or sink sprayer.

For this installation a 1/4″ hose was drilled into the face of the cabinet to bring the water supply line up. The hole can be filled, sanded & painted over should the owner relocate.

Water Ionizer Authority feels so strongly about this installation method that we offer the T-adapter at no charge when the part is requested at the time you purchase your water ionizer.   If you already have a water ionizer that you would like to reinstall using this method, the part can be ordered through Water Ionizer Authority for $20 – which includes the cost of shipping.  Please see the “accessories” section of our store to order this part.

Standard Parts

You will use the same installation parts that come with your water ionizer with the exception of the faucet adapter which may be ordered through Water Ionizer Authority.

If you are purchasing your water ionizer through Water Ionizer Authority we will include the T-adapter at no charge when requested the same day your order is placed.  Just reply to your order confirmation and request to have the part shipped to you with the unit.

This will go in the cold water line below the sink and is the part that diverts water from the main water supply line to your water ionizer.  You will still have water available at your faucet.

You will need the standard hosing that came with your water ionizer to supply water to the unit and to allow the waste water to drain into the sink.  If your water ionizer takes 3/8″ hosing you will also need a length of 1/4″ hosing to connect to the T-adapter.

Dispenser Hose
This is part of your water ionizer and will come with the unit.

These clamps are provided with water ionizers that use 3/8″ hosing.  They are “opened” by squeezing the “wings” or “tabs” – you can then slide the clamp over the hose, then once the hose is in place slide the clamp up over the hose/port connection.

Additional/Optional Parts/Tools

You’ll need these to remove the hose from the cold water line below the sink, secure the T-adapter and reconnect the cold water line securely.

Even though you’ll shut the cold water supply off before starting, there will still be some water in the line – having a towel handy to wipe up the drips is a good idea.

Teflon/Plumbing Tape
Optional – wrapping the threads at the cold water line connection will ensure a leak-free seal and is available for under $5 at most home improvement stores – sometimes you can even find it at larger grocery or drug stores.

Blanket or Padding
Optional but recommended!  Although you shouldn’t be under there for very long, working under the sink can be uncomfortable.  Having an old blanket or moving pad to place down there can make your working environment more comfortable – and soak up any drips that happen while installing the T-adapter.

Union Valve/Adapter
If your water ionizer uses a 3/8″ water supply hose you will need a 1/4″ to 3/8″ adapter to connect the 1/4″ line used by the T-adapter can connect to the 3/8″ hose used by your water ionizer.  Most water ionizers using a 3/8″ water supply line do not have a built-in “stop flow” mechanism.  This means that if water is flowing TO the unit, water is flowing THROUGH the unit.  The 1/4″ to 3/8″ union VALVE will connect these two lines AND will have a lever which you will use to allow water to flow through when you want to use your ionizer and will stop the water flow when you are finished with each use.

This adapter is available at almost any home improvement store or plumbing supply store.  Just specify “quick connect”   1/4″ to 3/8″ union adapter with valve.  “Quick connect” is known by most people working in the plumbing section as a “push in to connect” option and will look like the image shown here.

Getting Started

You’ll want to clear the area on your counter where you plan to place the water ionizer.

Cold Water Shut Off Valve

Things look a little different under every sink but you should see a line coming out of the wall with a knob or valve to open/close the water flow to the faucet.

Place the ionizer where you think you want it.

If you plan to put a hole in  your counter top, allow room for the hose to come up from under the sink and connect to the water ionizer.

Install the dispenser hose making sure that the unit is close enough to the sink for the hose to hang over the sink.  During cleaning cycles water will flow through this hose and if it is not close enough to the sink the water won’t have anywhere to go but on your counter.

Make any necessary adjustments to the placement of your unit so that the dispenser hose is able to reach over the sink.

Clear everything from UNDER the sink so that you’ll have plenty of room to work.

If you’re using a blanket or padding, lay it out -

Shut off the cold water supply:  I recommend turning the cold water on FULL at the tap, then turning the knob below the sink to shut off the water supply.  You’ll know you’re working at the correct water supply line when the water flow stops as you turn the knob to shut it off.  This will also allow excess water to drain from the cold water line which will reduce the drips while you’re working down there.


Remove the hose that runs from the cold water line (coming out of the wall) up to your faucet – have your towel handy – even if you’ve drained the cold water line by leaving the tap on, gravity ensures that there will still be some water in the line so be prepared with that towel.

Screw the T-adapter into the cold water line, wrapping the threads with teflon/plumbing tape if you are using it.  Use your pliers to ensure a tight connection.

Cold Water Line T-Adapter Installation Guide

The hose that connects the cold water pipe coming out of the wall to your faucet will have different sized fittings at each end. If the T-adapter doesn’t fit at one end of the hose, try the connection at the other end.

Reconnect the cold water line with the T-adapter in place – again, wrapping the threads with plumbing tape if you decide to use it.  Use your pliers to ensure a tight connection.

Connect the 1/4″ water supply hose to the T-adapter:  You will need to unscrew the fastener from the T-adapter and slip it onto the water supply line.

The 1/4″ line will be a snug fit going onto the T-adapter.  You can soften the end of the hose by soaking it in hot water for a few minutes.  NEVER USE OIL OR LUBRICANTS WHEN CONNECTING THE WATER SUPPLY LINE TO THE ADAPTER.

Once the hose is on the post of the adapter, slide the fastener up and screw it back on over the hose.  You will likely need your pliers to screw the fastener all the way on, ensuring a tight seal.

Open the valve on the T-adapter:  this valve will only move 45 degrees – you only want to open it a little more than halfway to ensure optimal flow rate to your water ionizer.

Secure the hose to the t-adapter by screwing the fitting back into place over the hose. Open the adapter valve a little more than halfway.


Bring the water line you just connected to the T-adapter up through the hole you made or have in your counter top or on your sink.

Stretching the hose out, measure how much line you need to connect to the water ionizer, be sure to leave a little slack for moving the unit around to change the filters or clean around it.

If you are using a 3/8″ hose with a union valve/adapter, measure the hose out to come close to the water ionizer with the union valve/adapter easily accessible for starting/stopping the water flow.

Once you’ve measured, cut the line.  Be sure to make a clean, flat, even cut to ensure a good seal to either the water ionizer or the valve/adapter.

When cutting the hose you want it to be as even as possible – no “points” or angles or “bumps” that might prevent a tight seal

All water ionizers will have “in/out” or “inflow/outflow” ports clearly labeled.

Connect the 1/4″ line to the “in” or “inflow” port on your water ionizer (or valve/adapter) by pressing in firmly.  Be sure you press the line in all the way – the hose will go in farther than you might think and if it is not in all the way the unit will leak.

"In" and "Out" ports will be labeled on your water ionizer

“In” and “Out” ports will be labeled on your water ionizer

If you are using the 1/4″ to 3/8″ valve/adapter you will need to insert one end of your 3/8″ hose in the adapter – turn the valve to the off position – cut the hose the appropriate length to reach the “in” port on your water ionizer and slide the hose over the in-port post and secure it with the clamps that came with your unit.

Connect water supply line

Be sure to press firmly to make sure the hose is all the way in!

Next, take the remaining length of hose and insert it firmly into the “out” or “outflow” port of your ionizer making sure you’ve inserted it all the way – for 3/8″ hose units you’ll slide the hose over the out/outflow post and secure it using the clamp that came with your water ionizer.

Connecting 3/8" hose

Proper connection for water ionizers using 3/8″ hose connections

Pre-run Check

I recommend opening the filter door to make sure there is a filter in there and then loosening it and re-tightening it to ensure it is installed properly.

Make sure the hose connected to the out/outflow port is hanging into your sink.

Make sure the dispenser hose is hanging over the sink.


Every water ionizer will have a power switch on the back or bottom of the unit.  Go ahead and flip the switch to the “on” position.

Plug in your water ionizer….

Duck back under the sink and turn the cold water back on – you’ll hear it running at the tap – then turn the water off at the tap.

Water is now being fed to your ionizer and it is ready to use!  Just press the on/off button or make a selection on the control panel to start the flow – this will depend on which water ionizer you have.

If you are using the 1/4″ to 3/8″ adapter/valve you will need to open the valve – once the valve is open, water will flow to and then through the water ionizer.

The first thing any water ionizer will do when it is first plugged in and turned on is run a cleaning cycle to flush the unit.

Often you will see water that is discolored for as long as several minutes as the filters are initially flushed out.  You should run your ionizer (at any setting) for a few minutes until there is no more discoloration in the water.

That’s it!  You’re installation is complete!

Now all you have to do to operate your water ionizer is press a button on the control panel.  If you are using the valve/adapter you will need to open/close the valve to turn the unit on/off.  Depending on which water ionizer you have it may also be necessary to press a button on the control panel to begin ionization.

Now you’re ready to test your water ionizer to ensure that you’re getting the pH level you want at each of the presets.  But you’ve done good work so far – treat yourself to a glass of water from your new ionizer first!

Please see our article “Tips for Testing” – it’s a useful guide for testing your water ionizer at each of the alkaline and acidic presets.

Tips for Testing Your Water Ionizer