Worcester Greenstar 21 Ri ErP+ Regular

Worcester Greenstar 21 Ri ErP+ Regular Boiler (Natural Gas)

The Worcester Greenstar 21 Ri ErP+ Regular Boiler is a compact, high-efficiency heating solution designed for homes with traditional open-vented heating systems and stored hot water cylinders. As part of Worcester Bosch’s trusted Greenstar range, it combines outstanding performance with sleek, space-saving design — perfect for homeowners who want reliability and energy efficiency in one neat package.

Compact, Powerful and Space-Saving

The Greenstar 21 Ri is one of the smallest condensing boilers in the Worcester Bosch lineup, small enough to fit neatly within a standard kitchen cupboard. Despite its compact dimensions — just 590mm high, 390mm wide, and 270mm deep — it delivers a robust 21 kW heat output, making it ideal for small to medium-sized homes. Its lightweight build, at just 27.4 kg, and multi-directional fluing options make installation simple and flexible, while flow and return pipes can be plumbed in from either above or below the unit for added convenience.

Energy Efficient and Eco-Friendly

With an ErP A rating and A-rated SAP 2005 seasonal efficiency, the Greenstar 21 Ri ensures excellent fuel economy and reduced energy costs. Designed with the environment in mind, it features low NOx and CO? emissions, contributing to cleaner air and lower carbon output. It’s also compatible with Worcester Greenskies solar panels, allowing households to incorporate renewable energy sources for even greater efficiency and sustainability.

Simple Controls and Reliable Performance

User-friendly and practical, this model includes a fascia-mounted heating temperature control knob and a neon operational status indicator, so you can easily monitor your system at a glance. Built to Worcester Bosch’s high standards, the Greenstar 21 Ri promises years of dependable heating with minimal maintenance.

Technical Specifications

• Model: Greenstar 21 Ri ErP+ Regular
• MPN: 7733600310
• EAN: 4057749719164
• Product Type: Heat Only (Regular) Boiler
• Fuel Type: Natural Gas
• Heat Output: 21 kW
• ErP Rating: A
• Mounting: Wall Mounted
• Colour: White
• Width: 390 mm
• Height: 590 mm
• Depth: 270 mm
• Weight: 27.4 kg
• Guarantee: 7 Years

Why Choose the Worcester Greenstar 21 Ri?

The Greenstar 21 Ri offers the perfect balance of performance, flexibility, and simplicity. It’s ideal for homes that need reliable central heating with a separate hot water cylinder. With its compact design, low emissions, and Worcester Bosch’s proven reliability, this boiler is a smart investment for long-term comfort and energy efficiency.

FAQs

Q1: What type of heating system does the Greenstar 21 Ri work with?

The Greenstar 21 Ri is designed for traditional open-vented heating systems that include a cold water tank and a separate hot water cylinder.

Q2: Can this boiler fit inside a kitchen cupboard?

Yes. The Greenstar 21 Ri is one of the smallest regular boilers on the market and can be installed neatly within a standard kitchen cabinet, saving valuable space.

Q3: How long is the warranty?

This model comes with a 7-year manufacturer’s guarantee (subject to installation and servicing conditions), offering peace of mind and long-term reliability.

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