BOSS 35L Expansion Vessel 3 Bar for Sealed Heating & Chilled Water Systems

Description

BOSS Expansion Vessel 35L (3 Bar) – Sealed Heating & Chilled Water Systems

The BOSS Expansion Vessel 35L (3 Bar) is a high-performance sealed expansion vessel designed for closed-loop heating systems and chilled water applications. Built to accommodate thermal expansion and contraction caused by changing water temperatures, it helps maintain stable system pressure, protect key components, and improve overall system efficiency.

Manufactured with a high-strength steel shell and a fixed butyl rubber diaphragm, the vessel effectively separates air and water to provide reliable pressure management and long service life. The integrated nitrogen-charged air valve with protective cap ensures dependable operation in residential, commercial, and light industrial installations.

Key Features

• 35 litre expansion vessel capacity
• Maximum working pressure: 3 bar
• Pre-charge pressure: 1.5 bar
• Fixed butyl rubber diaphragm
• High-strength steel vessel construction
• Nitrogen air valve with protective cap
• Suitable for sealed heating systems
• Suitable for chilled water systems
• Long service life and easy installation
• Compatible with water and glycol mixtures up to 50%
• CE Approved
• Manufactured in accordance with PED 97/23/EC and BS 4814:1990

Technical Specification

Applications

The BOSS 35L Expansion Vessel is suitable for:

• Sealed central heating systems
• Chilled water systems
• HVAC installations
• Residential heating systems
• Commercial heating systems
• Closed-loop heating and cooling circuits
• Plant room applications

Installation Guidance

For optimum performance, the expansion vessel should be installed on the coldest section of the system, typically the return pipework to the boiler, heat pump, or heat exchanger. Correct installation helps maintain accurate pressure control and maximise diaphragm lifespan.

Order Information

BOSS Expansion Vessel 35L (3 Bar)
Part Code: 19711074

Contact LoCO2 Heat for pricing, availability, and technical support.

Helpful Expansion Vessel Guides

Want to get the best performance from your expansion vessel? Our expert guides explain everything you need to know, from choosing the correct vessel size to setting and maintaining the right system pressure.

• Expansion Vessel Sizing: A Comprehensive Guide – Learn how to calculate the correct vessel size for your heating or chilled water system and avoid common sizing mistakes.

• Expansion Vessel Pressure Guide – Understand pre-charge pressure, system pressure requirements, troubleshooting tips, and how to maintain efficient system operation.

Read our guides before installation to ensure your system is correctly sized, pressurised, and protected.