1000 Litre Buffer Vessel or Tank

1000 Litre buffer vessel or tank

1000 Litre buffer vessel or tank from Flexiheat UK

Our 1000 litre buffer vessel or 1000 litre buffer tank is a hot water buffer tank or vessel that is typically installed to increase the volume of hot water in the heating system to store heated water.

Our buffer tanks or accumulator tanks are as such a thermal store for hot water systems and this energy is stored for later use, resulting in fewer but longer heating cycles for heat pump systems, wood pellet boilers, gasification boilers or a biomass heating system.

This is 1000 litre buffer tank is just one of our large range of buffer tanks and vessels . Our full large range of other size buffer tanks is detailed on this webpage – Buffer tanks

Heat pump systems

This buffer tank is ideal for use with heat pump systems, allow approximately 25 litres of volume per kW of heat pump output if the manufacturer hasn’t specified a buffer tank / accumulator tank volume.

Wood pellet boilers

For wood pellet boilers sizing – allow a minimum of 10 litres of buffer tank volume for every 1 kW of boiler output.

Gasification boilers

For gasification boilers or log fired biomass boilers – allow a minimum of 50 litres of  buffer tank volume for every 1 kW of boiler output.

1000 Litre Vessel – Buffer tank product description

This 1000 litre buffer vessel / accumulator tank is pressure rated to 8 Bar and maximum temperature of 95C for sealed heating systems and are not to be used on chilled water.

This 1,000L buffer vessel, or buffer tank is manufactured from mild steel or carbon steel. Please note corrosion inhibitors must be used on the heating water system to protect the product i.e. the buffer tank from corrosion .

Technical specifications of our buffer tanks / accumulator tanks are as follows –

1000 Litre Buffer vessel port details for the buffer plus range from Flexiheat UK to store heating hot water from various energy sources for peak demand use in hot water systems.

1000 Litre Buffer vessel / Accumulator tank / Cylinder thermal store for heating water


Buffer tank storage capacity – 1000 Litres nominal – 840 Litres Actual

Buffer tank height – 2,065 mm

Buffer tank pivot height – 2,270 mm

Diameter with Insulation: 940 mm

Diameter without Insulation: 790 mm

Pressure rating – 8 Bar maximum working pressure

This 1000 litre buffer vessel has a removeable insulation system, that allows you to get the unit through a standard 800mm wide door.

Removeable insulation system on our 1000 Litre buffer vessel Flexiheat UK

Product insulation is polyurethane – 75 mm insulation

Rigid expanded polyurethane insulation with 95% closed cells, CFC and HCFC free, fire resistance to class B2 according to DIN 4102-1.

The insulation is removable – which can help to get the buffer tank through doorways or access points

Great quality product at a great price and available from stock or on a short delivery

Buffer tank weight – 160 Kg when empty – 1,000 Kg’s when full with hot water

Eight tappings – 1 1/2″ female BSP, which enables the installation of immersion heaters as back up or top up heating

Four sensor or thermometer tappings – 1/2″ female BSP

1 x Air vent eliminator or safety valve tapping – 1 1/2″ female BSP

For full dimensions please see the following brochure –

Download the Buffer Plus range of buffer tanks and vessels brochure from Flexiheat UK

Contact Us

If you require further information, product availability, check stock levels, delivery times or prices on our 1000 Litre buffer vessel / accumulator tanks for sealed heating systems or other sizes from our large range of accumulator tanks, then please contact our sales service team on 01202 822221 or use our email contact form via the contact tab above to message us.

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