Harlequin HeatStream Electric Plus 150L Indirect Mains Hot Water System

Key Information

• 150-litre capacity — ideal for apartments, family homes, and modern properties
• Indirect thermal store design — incorporates a primary coil for alternative heat sources
• Open-vented thermal store — not subject to Part G Building Regulations
• 14-bar rated primary coil — suitable for district heating and higher-pressure applications
• Fast pre-heat capability — heats from a boiler in as little as 10 minutes
• Mains pressure hot water — delivers strong and consistent performance
• ErP B energy rating — supports efficient energy usage
• Low standing heat loss — only 1.12kWh per day
• Compatible with off-peak electricity tariffs — helps reduce running costs
• Suitable for use with solar PV systems — maximises renewable energy generation
• Compact 520mm x 520mm footprint — ideal for smaller airing cupboards
• Reduced legionella risk — supports improved water hygiene
• 5-year warranty — added peace of mind

What's Included

• Harlequin HeatStream Electric Plus 150L Indirect Mains Hot Water System - HS150E+

The Harlequin HeatStream Electric Plus 150L Indirect Mains Hot Water System is designed to provide reliable hot water while offering greater flexibility than standard electric thermal stores. With a 150-litre capacity and the ability to connect to an alternative heat source, it is ideal for apartments, family homes, and modern properties where efficient hot water production is a priority.

Its compact design and innovative thermal store technology make it a practical alternative to traditional hot water cylinders, particularly where installation constraints need to be considered.

Indirect Thermal Store with Additional Heat Source Capability

Unlike standard electric-only models, the HeatStream Electric Plus incorporates a primary coil that allows connection to an alternative heat source. This provides greater flexibility and can help improve efficiency by utilising existing heating systems, district heating networks, or other compatible heat sources.

The 14-bar rated primary coil is specifically designed to accommodate higher-pressure applications, making these thermal store cylinders suitable for a wide range of installations.

Simplified Installation

As an open-vented thermal store, the HS150EPLUS is not subject to Part G Building Regulations or the discharge requirements associated with traditional unvented systems. This removes the need for expansion vessels, temperature and pressure relief valves, and G3-qualified installation.

The system can be connected to an external overflow, a low-temperature internal waste pipe, or paired with an internal overflow solution where required.

Fast Heat Transfer and Excellent Performance

The primary coil can pre-heat the store in as little as 10 minutes when connected to a boiler or alternative heat source. Stainless steel corrugated coils with a large surface area provide exceptionally fast heat transfer, helping maintain a consistent supply of mains pressure hot water throughout the day.

This makes the system particularly effective in properties where demand can fluctuate during busy periods.

Efficient, Durable, and Low Maintenance

With an ErP B energy efficiency rating and standing heat losses of just 1.12kWh per day, the HeatStream Electric Plus is designed to minimise energy waste. It can also help maximise the benefits of off-peak electricity tariffs and solar PV systems where available.

The outer shell is manufactured from durable polyethylene, while the inner tank is constructed from non-corrosive polypropylene, making it ideal for areas with poor water quality. With minimal servicing requirements and a simple six-monthly top-up, ongoing maintenance costs remain low.

Ready to Upgrade Your Hot Water System?

If you're looking for versatile hot water cylinders that offer fast recovery, simplified installation, and compatibility with alternative heat sources, the Harlequin HeatStream Electric Plus 150L is an excellent choice.