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BOSS 12L Expansion Vessel 3 Bar for Sealed Heating & Chilled Water Systems

Original price was: £113.34£94.45.Current price is: £52.30£43.58. £52.30£43.58 inc VAT Incl. VATExcl. VAT

Product Code: 19711041

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Description

BOSS Expansion Vessel 12L (3 Bar) – Sealed Heating & Chilled Water Systems

The BOSS Expansion Vessel 12L (3 Bar) is designed for sealed heating systems and chilled water applications, providing reliable accommodation of thermal expansion and contraction within closed-loop systems. By maintaining consistent system pressure, it helps protect boilers, pumps, valves, and other essential components while supporting efficient and safe operation.

Manufactured from a high-strength steel shell and incorporating a fixed butyl rubber diaphragm, the vessel effectively separates air and water to ensure dependable pressure management and long service life. Suitable for use with water and glycol mixtures up to 50%, it is ideal for residential and light commercial installations.

Key Features

  • 12 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

Specification Value
Capacity 12 Litres
Maximum Working Pressure 3 Bar
Pre-Charge Pressure 1.5 Bar
Connection Size ¾” BSP Male
Diameter 280 mm
Height 290 mm
Weight 4.3 kg
Part Number 19711041

Applications

The BOSS 12L Expansion Vessel is suitable for:

  • Sealed central heating systems
  • Chilled water systems
  • Residential heating installations
  • Light commercial heating systems
  • HVAC applications
  • Closed-loop heating and cooling circuits

Compatible Mounting Bracket

For a secure and professional installation, the BOSS 12L Expansion Vessel can be paired with the BOSS Expansion Vessel Mounting Bracket (Part No. 19713001). The bracket provides stable wall mounting, simplifies installation, and helps reduce stress on connecting pipework.

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 service life.

Order Information

BOSS Expansion Vessel 12L (3 Bar)
Part Code: 19711041

Compatible Mounting Bracket: 19713001

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.

Additional information

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The documents and links below provide installation guidance and product information to support the use of this product.

BOSS RED SEALED EXPANSION VESSELS – DATA SHEET (PDF) BOSS Red Sealed Expansion Vessels – Installation & Operation MANUAL (PDF) BOSS Red Sealed Expansion Vessels – Declaration of ConformitY (PDF)

Supporting guidance on sizing and pressure setup:
Expansion vessel sizing guide
Expansion vessel pressure setting guide

BOSS 12L Expansion Vessel 3 Bar for Sealed Heating & Chilled Water SystemsBOSS 12L Expansion Vessel 3 Bar for Sealed Heating & Chilled Water Systems
Original price was: £113.34£94.45.Current price is: £52.30£43.58. £52.30£43.58 inc VAT Incl. VATExcl. VAT

Enquire for lead time

GET YOUR TRADE DISCOUNTS