Varem R8018241S4000000 - Solar expansion vessel (18L)

Expansion vessel for solar thermal systems

The Varem R8018241S4000000 solar expansion vessel (18L) is designed for use in solar thermal systems. It absorbs volume changes in the solar circuit caused by temperature fluctuations in the fluid. This helps keep system pressure under control and protects the installation from unnecessary stress.

Suitable for glycol-based solar circuits

This solar expansion vessel is suitable for systems using glycol in the fluid circuit. It can be used in installations with up to 100% glycol, making it suitable for solar hot water and solar thermal systems that require frost and high-temperature protection.

Replaceable membrane

The expansion vessel is equipped with a replaceable membrane. This makes maintenance and service easier and extends the practical service life of the component within the installation.

Stainless steel connection flange

The connection flange is made from stainless steel, providing a durable and corrosion-resistant connection within the solar circuit. This is especially important in solar thermal systems with high temperatures and glycol-based fluids.

18 litre capacity

With a capacity of 18 litres, this Varem solar expansion vessel is suitable for small to medium-sized solar thermal systems. Correct sizing depends on collector area, pipe volume, glycol percentage and operating pressure.

Sizing guideline

As a general guideline, allow at least 1 litre of expansion volume per m² of collector area for flat plate collectors and at least 2 litres per m² for vacuum tube collectors. This guideline does not replace professional system planning.

Support from Hewa

Hewa supplies solar expansion vessels, solar collectors, solar stations and installation components for professional solar thermal systems. Installers can rely on technical advice and suitable products for complete solar hot water projects.