If you want all that mixer performance taking its supply from a hot water tank or combi boiler has to offer an electric shower may disappoint. This Host unit includes a wireless shower controller. From €445 at the Bath Shack, bathshack.com

The latest electric showers are no bedsit compromise, and savvy families have long recognised their use as a primary or secondary shower for instantaneous hot water at a touch. 

If you’ve investigated and found your water pressure to be feeble or you cannot summon enough hot water for multiple simultaneous showers, they present an easily installed, economical solution, now with looks and impressive thermostatic performance to match.

Electric showers act as a water heater and can ratchet up the pressure where a gravity-fed domestic supply is struggling.

When is low pressure, truly low? Whether you’re putting in or renovating a bathroom or renovating, water pressure and the water system type will guide your choice.

An adequate delivery of water in a sufficient quantity to caress and soak your body and hair thoroughly for several minutes at a consistent temperature is crucial to a comfortable drench. Good pressure to a showerhead comes in around 12l-15l a minute, and bar pressure (determined by a pressure gauge) is determined as high at one bar or more.

In a traditional gravity domestic water system with a water tank in the attic and a cistern in the hot press, headage is the distance between the bottom of the water tank in the attic and the showerhead.

One-metre headage is unlikely to deliver good pressure (flow rate) and small diameter old pipes can further constrict the system’s water flow.

They only need a cold mains supply

Separating your shower from the other hot water demands of your main domestic water system is a neat trick. Adding an extra bathroom and using an electric shower – it simplifies the plumbing to just a cold supply to the attic or a distant bedroom.

Electric showers bypass the expensive vagaries of an immersion switch in a busy household reliant on a gravity-fed water supply and cylinder, as they only heat the water that’s needed.

A thermostatic electric shower can be set to one temperature and flow without the concern of a draw elsewhere in the house sending you skyward with an abrupt temperature change. If you thought with an electric shower you couldn’t have a gorgeous diverter with a principle overhead showerhead; may I divert you to the Mira Décor Dual in White, Warm Silver or Black Onyx (mains fed only I’m afraid), €370, multiple suppliers.

Ideal for low/erratic pressure situations

Where you don’t want to fix the whole house pressure, a pumped electric shower can bring the flow rate up to as much as 6l per minute at 9.5kWs. If your pressure is fine, simply choose a model designed to work off the mains.

If you have a tanked supply with low pressure choose a pumped model to work from the reserved supply (slightly more expensive). Keep in mind as we are using a cold water supply, an electric shower increasing the water pressure to that head, as well as heating the water instantaneously, will draw down more power to deal with colder water in the wintertime.

Power showers can’t be used for combi-boilers where there’s no storage cylinder.

Where your combi-boiler is struggling to supply enough hot water for a second running shower (and you’re not ready to scale up the boiler), an electric shower taking water from the cold rising mains supply can quieten teenage whining. You can alter the flow rate and heat directly on the unit controls. Using the mains, we need around 0.7bar pressure at a minimum to run an appropriate electric (non-pumped) shower heating the water as it goes.

Electric showers can be energy savers

The power and running cost of a pumped electric shower will depend on the kW rating which rises to around 10.5kW. With lower flow rates than most power showers, electric pumped showers tend to be more energy-efficient than power showers when sanely used over three-five minutes.

Even a photovoltaic panel will need mains power to run an electric shower as there’s a limited possible draw-down of supply from any inverter/battery. With a kW rating and given your family size and showering habits, you can work out fairly closely what the shower is likely to cost to run (water charges aside). No electric shower will knock you off your feet as the flow rates are generally far lower than a good mains pressure or pumped mixer, saving water usage. Ensure you check your current electricity tariff and switch up every 12 months for new time-of-use tariff deals.

The look of electric showers has improved out of all recognition from the buzzing, identical showers of the 1980s and 1990s, with glass and metallic fronts now offered together with the sleek white housings of an entry-level unit.

Remote-control Bluetooth with digital touch control has even allowed for the working electronics to be housed in the attic or airing cupboard, delivering an almost flat, very sleek face to some shower units.

This is great when you want to upgrade the shower without chasing wires back into the existing tiling.

Every shower will be temperature stabilised for a safe, balanced temperature within five degrees during use.

However, where the cold water supply is under duress because of voltage and supply fluctuations (especially for showering children and the elderly) consider a thermostatic electric shower for total peace of mind. 

Digital control pads allow you to set your favourite temperature, even allowing for multiple personal settings. Take a look at the Triton T300S1 with remote Bluetooth connectivity (up to 3.5m). From for a 9.5kW, €397, tritonshowers.ie

The choice of units and shower heads

Mixers and digital showers offer a larger choice of control panels, jets, diverters and overhead sprays. Gravity-fed electric showers in particular (not working off the rising mains) come in just a few models. The Triton T90sr (for silent running) is one of the most popular, easily changed out for the old T90z (from €299 at the Bathshack).

At 9kW it won’t shake up any light stud-work. With a modest flow, even allowing for aeration, the supplied head of an electric shower is likely to be relatively small, so manage your expectations.

Smaller, more multiple holes in the head can create the ‘feel’ of more pressure but not greater flow.

Mains-fed pressure blasts the competition

Combi-boiler systems termed high pressure vented, and mains pressure unvented systems with a dedicated strengthened hot water cylinder (say matched to a heat pump) will easily and economically serve 0.5bar-2 bar mixer showers. If you want a skin pummelling deluge of 15l plus and multiple body sprays, an electric shower will probably prove a disappointment.

Other solutions to low-pressure problems

There are alternatives to allow you to use a wider choice of shower styles. For low gravity-fed or even mains pressure - have a reputable plumber check the system for any anomalies interfering with the supply like an obstructed shut-off valve. They will check the static and maintained pressure and address any inconsistencies.

A remotely sited booster pump can add muscle to multiple showers and taps all over a gravity-fed house. Working with a traditional hot water cylinder, we’ll need enough volume of preheated water to tolerate aqua-fiends who won’t drop the soap in less than 15 minutes.

Whole-house pumps come in at €180-€600 depending on brand and power, ex installation and complicating plumbing feats. Single twin-headed shower pumps can finesse a single bathroom (1.5lbar Salamander €130 ex installation). Adding any booster pump to an unvented system is complex and involves introducing a break tank, talk to your plumber.

A power shower with an integral pump inside its housing to (again) can shove along your pre-heated hot (cylindered) water. With the pump thrumming in the unit, they can be noisy. The difference between the power shower and a pumped electric shower (working as a water heater) is that the power shower must draw off an existing hot and cold supply, and with a busy, mucky family; this leaves us right back at an empty tank and a terrifying bill for an ancient immersion.

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