Ariston Andris Lux 10L Undersink Unvented Water Heater 3kW – 3100303

The Ariston Andris Lux 10L Undersink Unvented Water Heater 3100303 provides compact, point-of-use hot water beneath a sink or basin. It suits kitchens, utility rooms, offices, workshops, garages, washrooms and other locations with limited space.

A powerful 3kW heating element heats the 10-litre tank in approximately 12 minutes. Therefore, this model provides faster recovery than the 2kW version and suits locations that need hot water more frequently.

The Andris Lux combines Italian styling with simple mechanical controls. In addition, its titanium-enamelled tank, strong four-bolt flange and effective insulation support reliable performance and long-term durability.

This model fits below the sink with its water connections positioned at the top. Therefore, check that you need an undersink water heater before ordering.

Product Guides and Further Information

• Download the Ariston Andris Lux installation and user manual
• View the official Ariston Andris Lux range
• View Ariston warranty and registration information

Ariston Andris Lux 10L Undersink Water Heater Features

• Compact unvented electric storage water heater
• Manufacturer model number: 3100303
• 10-litre stored water capacity
• Designed for undersink installation
• Top-facing water connections
• Powerful 3kW copper heating element
• Approximate heat-up time of 12 minutes
• Simple external mechanical temperature control
• Energy-saving setting on the control dial
• Heating indicator shows when the element operates
• Titanium-enamelled tank for added protection
• Strong four-bolt flange construction
• Compact Italian design
• ERP energy rating: B
• Expansion relief valve supplied
• Suitable for domestic and light commercial applications
• Three-year tank warranty, subject to Ariston’s terms
• One-year electrical-parts warranty, subject to Ariston’s terms

Technical Specification

• Manufacturer: Ariston
• Range: Andris Lux
• Model: 3100303
• Product type: Unvented electric storage water heater
• Installation position: Undersink
• Capacity: 10 litres
• Element rating: 3kW
• Electrical supply: 220–240V
• Approximate heat-up time: 12 minutes
• ERP energy rating: B
• Tapping profile: XXS
• Standing heat loss at 65°C: Approximately 0.71kWh per day
• Maximum working pressure: 6 bar
• Empty unit weight: Approximately 6.7kg
• Water connections: 1/2-inch BSP
• Connection position: Top of the heater
• Control type: External mechanical dial
• Heating indicator: Yes
• Expansion relief valve: Supplied

Water Heater Dimensions

• Body height: Approximately 360mm
• Overall installation height: Allow approximately 385mm before pipework clearance
• Width: 360mm
• Depth: 298mm

Before ordering, measure the cupboard and allow enough room above the heater for its top connections, valves and pipework. Also, leave suitable access at the front for temperature adjustment and future servicing.

What Comes with the Water Heater?

• 1 x Ariston Andris Lux 10L undersink water heater
• 1 x expansion relief valve
• Wall-mounting bracket or fixing components
• Installation and user information

The installer may need additional controls, valves or an Ariston installation kit. The exact requirements depend on the incoming water pressure, pipe arrangement and available expansion within the system.

Ariston Installation Kits You May Need

• Kit A: Two-litre expansion vessel and non-return valve
• Kit B: 3.5 bar pressure-reducing valve
• Kit C: Discharge tundish

For example, the installation may require Kit A when the cold pipe does not provide enough space for thermal expansion. In addition, the system may need Kit B when the incoming mains pressure exceeds 3.5 bar.

Requirements vary between properties. Therefore, ask a competent installer to inspect the proposed installation before ordering the heater and any accessory kits.

Where Can You Use the Ariston Andris Lux 10L?

The Ariston Andris Lux 10L provides local hot water where demand remains relatively low. Consequently, it can reduce delays and water waste caused by long pipe runs from a central hot water source.

• Domestic kitchens and utility rooms
• Office kitchens and staff rooms
• Workshops and garages
• Loft conversions and annexes
• Shops and small commercial premises
• Washrooms and handwashing basins
• Doctors’ and dentists’ surgeries
• Locations far from the main hot water system

This 10-litre model works best for light point-of-use demand. However, it may not suit showers, baths or applications that require large and continuous volumes of hot water.

Undersink or Oversink Water Heater?

This model is an undersink water heater, so the installer positions it below the sink or basin. Its water connections face upwards from the top of the unit.

In contrast, an oversink model fits above the outlet and has connections positioned underneath. Therefore, oversink and undersink heaters are not automatically interchangeable.

Benefits of an Unvented Water Heater

An unvented point-of-use heater connects directly to the mains water supply. As a result, it can work with suitable standard taps and does not need a special open-outlet vented spout.

In addition, local installation shortens the distance between the heater and outlet. This arrangement may reduce waiting time and the amount of cold water wasted before hot water reaches the tap.

However, unvented installation requires the correct safety and expansion controls. A competent installer must check the incoming water pressure and follow the latest Ariston installation instructions.

Fast 3kW Water Heating

The 3kW element provides quicker recovery than the 2kW model. Ariston states an approximate heat-up time of 12 minutes under its test conditions.

However, actual recovery time can vary with the incoming water temperature, thermostat setting and electrical supply. The installer must confirm that the circuit and protective devices can safely support the 3kW load.

2kW or 3kW Andris Lux?

The 2kW and 3kW undersink models both store 10 litres of water and use the same compact enclosure. However, the 3kW version heats the water more quickly.

In contrast, the 2kW model draws less electrical power while heating. Therefore, your choice should depend on the required recovery time and the electrical supply available at the installation point.

Simple Temperature Control

The external mechanical dial makes the heater straightforward to operate. In addition, the energy-saving setting helps balance hot water comfort with lower energy use.

A heating lamp shows when the element operates. Therefore, users can easily see when the unit is warming the stored water.

Why Choose the Ariston Andris Lux?

The Andris Lux range combines compact dimensions, simple controls and practical point-of-use water heating. Therefore, it offers a useful solution where space remains limited or the main hot water source sits far from the outlet.

First, the titanium-enamelled tank helps protect the internal vessel. Next, the mechanical dial provides simple temperature adjustment. Finally, effective insulation helps retain the stored heat.

Why Buy from SNH Tradecentre?

• Competitive prices: We aim to offer excellent value across the Ariston water heater range.
• Helpful advice: Our team can help you compare 2kW, 3kW, oversink and undersink models.
• Genuine Ariston products: Buy from an established plumbing and heating merchant.
• Installation accessories: We can help you identify the Ariston kits that your installer may require.
• Clear information: We provide useful specifications and installation documents.
• Trade and public welcome: We supply homeowners, landlords, plumbers and professional installers.
• Independent merchant: SNH Tradecentre operates from Birchington, Kent.

Need Help Choosing?

Not sure whether you need a 2kW or 3kW water heater? Call SNH Tradecentre on 01843 842727. Our team can help you compare the available Ariston models and installation kits.

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Installation Requirements

A competent plumber and electrician must install and commission this unvented water heater. The installation must follow current electrical, water and Building Regulations together with the latest Ariston instructions.

The installer must check the incoming water pressure and available pipework expansion. Depending on the installation, they may need a pressure-reducing valve, non-return valve, expansion vessel or tundish.

The expansion relief valve requires a safe and visible discharge route. Furthermore, a qualified electrician must provide the correct isolation and circuit protection for the 3kW element.

Do not connect the heater to the electricity supply until the tank is completely full of water. Switching on an empty heater may damage the heating element.

Warranty Information

Ariston provides a three-year warranty on the tank and a one-year warranty on electrical components, subject to its current terms. Ariston may require product registration within 30 days of commissioning and regular professional servicing or inspection.

Keep the purchase receipt, installation details and service records. In addition, register the product with Ariston after installation to help protect the manufacturer’s warranty.

Frequently Asked Questions

Is model 3100303 an oversink or undersink heater?

Model 3100303 is an undersink water heater. Therefore, it fits below the sink with its water connections positioned at the top.

Is the Ariston Andris Lux 10L vented or unvented?

This model is an unvented storage water heater. Therefore, it connects to the mains and requires the correct pressure, expansion and safety controls.

How much water does this heater store?

This model stores 10 litres of hot water. It suits sinks, basins and other light point-of-use applications.

How powerful is the heating element?

The heater contains a 3kW element. A competent electrician must confirm that the electrical circuit and protective devices suit the appliance.

How quickly does it heat the water?

Ariston lists an approximate heat-up time of 12 minutes under its test conditions. However, the actual time depends on the incoming water temperature and thermostat setting.

What energy rating does the heater have?

The Ariston Andris Lux 10L 3kW undersink model has a B energy rating and an XXS tapping profile.

Does it include an expansion relief valve?

Yes. An expansion relief valve comes with the heater. However, the installation may require additional Ariston kits and safety controls.

Do I need an expansion vessel?

That depends on the installation and available pipework expansion. For example, a non-return valve or short pipe run may mean that the system needs Ariston Kit A.

Can it supply more than one outlet?

The heater may supply suitable nearby outlets when the installation meets Ariston’s requirements. However, its 10-litre capacity limits the stored water available when users open several outlets close together.

Can it supply a shower?

This compact heater primarily suits sinks, basins and light point-of-use demand. It does not normally provide enough stored hot water for a standard shower or bath.

Who can install this water heater?

A competent professional should complete the plumbing and electrical work. They must follow current regulations and Ariston’s latest installation instructions.

What warranty does the Andris Lux include?

Ariston provides a three-year tank warranty and a one-year electrical-parts warranty, subject to registration, servicing and its current terms and conditions.

Order the Ariston Andris Lux 10L Undersink Heater

Choose the Ariston Andris Lux 10L Undersink Unvented Water Heater 3kW 3100303 for compact point-of-use hot water, fast recovery and discreet installation below a sink.

Before ordering, ask your installer to confirm the mounting position, water pressure, electrical supply and installation-kit requirements. Then, contact SNH Tradecentre if you need help choosing the correct model.

Ariston may update specifications, packaging and supplied components without notice. Therefore, check the latest manufacturer literature before ordering or installing this water heater.