Zilmet CAL-PRO Heating Expansion Vessels
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The Zilmet Cal-Pro Expansion Vessel is a robust, maintenance-free solution designed to manage thermal expansion in closed-loop heating systems. By absorbing excess pressure caused by heated water, it protects boilers, pipes, and radiators from damage, ensuring efficient and reliable operation.
Key Specifications
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Capacity Range: 8–35 litres (suitable for small domestic to light commercial systems).
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Maximum Working Pressure: 10 bar / 145 psi.
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Factory Pre-Charge Pressure: 1.5 bar / 22 psi (adjustable for system requirements).
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Maximum Temperature: 100°C / 212°F.
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Connection Size: 1" BSP female thread (standard for UK heating systems).
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Diaphragm Material: High-grade nitrile rubber (resistant to wear and corrosion).
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Shell Material: Carbon steel with epoxy-coated finish for durability.
Features & Benefits
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Pressure Stabilisation: Prevents pressure spikes in heating systems, extending equipment lifespan.
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Compact Design: Space-saving and easy to install in boiler rooms or compact spaces.
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Adjustable Pre-Charge: Customisable to match system static pressure.
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Corrosion-Resistant: Epoxy coating protects against rust in damp environments.
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Compliance: Meets UK and EU standards for heating system components.
Typical Applications
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Domestic and commercial boiler systems.
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Underfloor heating circuits.
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Solar thermal installations.
Installation Notes
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Mount vertically to optimise diaphragm performance.
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Ensure pre-charge pressure matches system static pressure before installation.
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Consult a Gas Safe registered engineer for compliance with UK building regulations.
- Type Expansion Vessel for Heating Systems
- Vendor Zilmet
- SKU EVP4
