10 Best Tankless Water Heaters 2025 in the UK

The Stiebel Eltron DCE-X Premium Compact Instant Water Heater is a notable option for those seeking a compact and efficient tankless water heater, ideal for shower use. This model stands out with its emphasis on energy efficiency, thanks to its 4i technology and fully electronic closed-loop control, which ensures accurate temperature delivery and maximum energy efficiency. The inclusion of an ECO mode further enhances its energy-saving credentials, making it particularly attractive for users conscious of their energy consumption.

The unit's design is sleek and modern, with a large, backlit multifunction display that simplifies operation, making it user-friendly even for those not familiar with advanced electronics. The size and weight of the heater are within a reasonable range, with dimensions that suggest it should fit easily into smaller spaces, although installation might require professional assistance due to its electrical requirements.

Some potential drawbacks include the specific voltage requirements of 220-240V, which may limit its use in certain regions without the appropriate electrical infrastructure. The 10/12 kW power specification suggests a moderate flow rate, which should be considered for households with higher hot water demands or multiple simultaneous users. While it ranks decently in its category and has positive customer reviews, prospective buyers should consider the specifics of their water heating needs, particularly in terms of flow rate and installation capabilities, to ensure this model meets their requirements. It's a strong contender for those needing a reliable and efficient water heater for personal or small-scale use.

The Briwellna Electric Instantaneous Tankless Water Heater is a compact and energy-efficient option designed for specific applications like single sensor faucets or metering faucets for handwashing. Its compact size (7.3 cm height) allows for easy installation in tight spaces, making it a good replacement for older, bulkier models. The flexibility in installation orientation and the digital display that adjusts automatically are notable features that add convenience.

This unit operates on 220V and requires a dedicated 25A double pole breaker, so ensure your electrical setup can support it before purchase. With a 5.5 kW power rating, it delivers on-demand hot water without the need for storage or preheating, which means it saves both energy and time. However, this also means it might not be suitable for larger households or applications requiring high flow rates.

Safety features like protection from leakage, over-temperature, dry heating, and over-pressure are built-in, adding an extra layer of security. The product has received mixed reviews with an average rating of 3.6 out of 5 stars from 124 customers, indicating a satisfactory performance for its intended use. It is best suited for users needing hot water for specific, low-demand tasks rather than whole-house use.

The Stiebel Eltron 234407 SHC 15 GB is a small, electric tankless water heater designed mainly for under-sink installation or for supplying one or a few outlets. Its compact size makes it ideal for tight spaces, measuring about 45 cm tall and weighing under 5 kg. This model offers a 15-liter tank capacity with a maximum temperature of 65°C, providing a steady warm water supply but limited in flow rate since it’s not designed for multiple high-demand points at once.

The heater is highly energy efficient with an ErP A rating, helping reduce electricity use compared to less efficient models. Since it runs on electricity, it’s convenient for homes without gas but might increase electric bills if used heavily. Installation requires wall mounting and can include an optional expansion kit if more water points are needed.

This unit is well suited for small kitchens or bathrooms with moderate hot water needs but is not appropriate for larger households or situations requiring high flow rates. The 2-year warranty adds peace of mind, and user reviews suggest good reliability. It is a compact, energy-saving water heater intended for limited hot water usage rather than a full-house solution.