InSinkErator 4n1 Touch review: why I’m now a convert to the cult of the boiling water tap

Welcome to our nuts-and-bolts review of the Insinkerator 4n1 Touch, a boiling water tap system that makes first-world domestic life go with a zing. 

The boiling water tap was allegedly invented in 1970 by a Rotterdam-born chap named Henri Peteri who, incidentally, escaped Nazi occupation of the Netherlands in a hand-assembled kayak. With the help of his two sons Walter and Niels, Henri started the brand Quooker and spawned a revolution in boiling tap water systems that others would soon follow.

Take InSinkErator, for instance, a company that goes all the way back to 1927 when its Wisconsin owner John W Hammes first invented the mechanical food waste disposal unit. Fast forward a few decades and, in 1973, InSinkErator developed its own brand of boiling water tap and the rest is history. Since 2013, the company has been near the forefront of both domestic and professional kitchen waste disposal and boiling water systems and in 2018 it launched the 4N1 Touch boiling water tap which we are reviewing right here.

Insinkerator 4n1 Touch review: what is a boiling water tap?

A boiling water tap is just that, a tap that produces a steady stream of boiling water for whenever you need it. With a boiling water tap in situ, you will never need to use a kettle again.

A boiling water tap has many uses. Firstly, the water is hot enough to make a cup of tea (about 99˚C) without it developing a scum which is usually a sure sign that the water isn’t hot enough. Secondly, it can also be used to fill a saucepan so that far less time is spent bringing the water to a boil when cooking on a hob. Other uses include instant sterilisation of kitchen implements, cutting boards and knives. In most systems like the InSinkErator 4N1 Touch, the hot water is also filtered so your vegetables and cups of tea aren’t tainted by calcium deposits and other minerals.

Some models like the InSinkErator 4N1 Touch also come with a filtered cold water function. Aside from being a brilliantly convenient way to access spotlessly clean drinking water 24/7, the tap can also be used to refill a coffee machine, a steam iron and any other product that usually requires descaling on a regular basis.

Contrary to what you might assume, running costs are pretty minimal and most manufacturers will say that running a boiling water system is cheaper in the long term than boiling a million kettles. In fact, according to N Power, the average cost to boil a full kettle of water is 2.5p whilst a boiling water tap costs as little as 1p per litre.

In short, a very small, heavily insulated boiler situated under the sink continually tops up the temperature so that the water is always ready for use, rather like your home combi boiler produces hot water. However, unlike a normal tap which takes about 20 seconds for the hot water to come down the pipe, with a boiling water system steaming hot water streams out of the tap the moment you activate it. In most instances, the boiling water is assigned to a separate tap and, furthermore, the tap itself will always be equipped with a safety mechanism so you don’t end up scalding yourself.

Now you know how it works, let’s get down the nitty gritty of the InSinkErator 4N1 Touch.

Insinkerator 4n1 Touch review: design and features

Designed and and built in Italy, the 4n1 Touch is available in three different tap designs – J shape, L shape and U shape – and three finishes – Chrome, Velvet Black and Brushed Steel.

I opted for the traditional J shape which is better suited to a country-style kitchen. But if your home is of modernistic design, perhaps go for the L or U shape options which are well suited to Grand Design-style kitchens with Scandinavian-style minimalism.

The build quality of the InSinkErator 4n1 Touch is exemplary and everything about it screams quality of the highest order. The chrome model I opted for is stunningly shiny and ultra smooth, and very easy to keep clean with just a quick wipe.

The swivelling J-shape model on test is about 39cm tall (just over 15 inches) and comes with a reach of 21 cm (about 8 inches) so it will easily swivel over a twin-sink system if positioned centrally.

Positioned near the bottom of the tap is a touch-sensitive button that activates the cold filtered water function. Simply tap it to start and tap to stop. The flow will automatically cut off after 30 seconds if left running.

Before you can indulge in the befits of have boiling water on tap, you’ll be required to have a mini boiler and water filter unit fitted under the sink by one of InSinkErator’s countrywide installers. The 2.5-litre boiler housing measures just 28cm x 15cm so it doesn’t take up much room. However, depending on the size of your cupboard and your current plumbing assembly, the installer may have to remove the cupboard’s main storage shelf in order to plumb in the boiler and the accompanying water filter assembly. See more on that below.

The boiler itself features an on/off button and a sliding-scale temperature gauge. The boiler’s factory pre-set temperature is 96˚C but you can adjust it yourself from 88˚C to 99˚C. The recommended water supply pressure is between 1.7 and 8.6 bar.

The accompanying water filter should be replaced every six months or so, especially if you use the drinking water function a lot. At £75 for two, the filters are actually quite keenly priced when compared to other brands.

Insinkerator 4n1 Touch review: installation

Before ordering an InSinkErator 4n1 Touch, be sure you have enough space under the sink. In fact, InSinkErator’s installer may ask for a photo of the space beneath your sink before proceeding with the installation.

We have a traditional ceramic twin sink system with a double cupboard beneath. Although we did originally have a dividing shelf underneath, this had to be removed to accommodate the boiler, water filter assembly and extra pipes. It literally depends on the space in your cupboard and how tidily your under-sink plumbing is arranged. Personally I’m not too bothered about losing the shelf because it encouraged me to fill it with lots of items I’ve never used.

Installation cost for the 4n1 Touch is about £180 though you will need to spend a bit more on an electrician to instal a plug socket under sink to power the boiler. This should be done before the InSinkErator is installed.

Insinkerator 4n1 Touch review: how it works

At first glance the 4n1 Touch looks like a standard twin tap system with leavers for hot and cold on either side. However, in this instance the lever on the right is a dedicated mixer tap for both hot and cold mains water. The lever itself is superbly engineered so it has a slightly stiff but forgiving action that, once mastered, allows the user to keep the lever in the ‘magic spot’ for a perfect hand temperature. The water is slightly aerated, too, so it doesn’t splash out of the sink bowl when it hits something like an upturned spoon.

The identical looking lever on the left is where all the boiling water action occurs. For safety reasons, you have to push the lever downwards firmly followed by a forwards pull to activate the boiling water. This is a great safety system to have and, to date, I’ve had no confusing moments where I’ve accidentally activated the wrong tap. Yes, it takes a few days to train the brain, especially if your previous tap system was of similar design, but the decisive nature of having to firmly push down on a lever is a damn good safety element that, to me, is as safe as it’s possible to be. Furthermore, the heavily sprung lever ensures complete control over the flow pressure which, even at full bore, is so perfectly dialled the water doesn’t splash all over the place. I’ve pre-heated many small espresso cups using the boiling water tap and I haven’t scalded myself yet.

One of the very best things about this model is that it’s equipped with a cold filtered water function. Simply tap the tip of your index finger against the button near the bottom of the tap and, voila, instant cool filtered water. To stop the flow, tap it again. If you leave the water running, the flow will automatically stop after 30 seconds. Just be sure to use a tapping action rather than a pushing action when activating the filtered water function or it may not work.

Insinkerator 4n1 Touch review: verdict

I honestly never thought I’d ever need a boiling water tap or even a filtered mains water system. But since having the Insinkerator 4n1 Touch installed, I’m finding it amazingly convenient. Yes it’s first-world convenience but I’m very much liking the time it saves in waiting for a kettle to boil and I’m especially loving the filtered water feature which filters out hardness, limescale and other impurities to make even our unappealing Thames water taste better than some bottled waters. In fact, the water that now comes out of my tap has almost the same silkiness as my favourite mineral-free Aqua Carpatico still water.

So far my partner and I have used the cold water feature for drinking, to fill both coffee machines and the steam generator, and to give our dogs and cats a better class of drinking water. Perhaps more importantly, we’ve also used the boiling water system on a regular basis to fill saucepans with pre-heated water ready for a quick boil on the hob, to rinse cutting knives under the tap, to pre-heat the espresso machine’s portafilter and warm the cups, and to soak grubby roasting pans in the sink. I’m particularly impressed with the way the water flow is so easily controllable and, as mentioned above, I’m pleased to announce that, to date, I haven’t once scalded myself. Fingers crossed!

At roughly £1,300 without installation, the cost of the InSinkErator 4n1 Touch is tough to justify when you can continue to simply boil a kettle and drink bottled water. However, like most things that seem unjustifiably expensive at first but soon become something you can’t live without, the InSinkErator 4n1 Touch inveigles itself into your everyday domestic life and before long you’re hooked.

Looking for a different brand or model? Check out our guide to the Best Boiling Water Tap.