Heat Accumulator

Innovative storage concept for heating water

Capacities from 3500 L to 17500 L as standard
Supplied in kit form, easy assembly on site
For indoor and outdoor use
Suitable for multivalent systems.

Environmentally responsible heat pumps – learn more about the different versions and benefits!

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3500 to 17500 L as standard. Customs configurations on request

Easy transport

All components supplied as flat pack, fir through a standard door way

Easy to install

Quick assembly using no specialised tools


Heating water stored at atmospheric pressure

High DHW convenience

Instantaneous DHW production in SS 316 coils, no risk of legionella


Robust construction and log service life

Energycal LSQ Modular Heatpump

Thermocube: Large capacity heat accumulators for DHW production

The THERMOCUBE ™   is a patented Hot Water Heat Accumulator (buffer tank) system, constructed from interlocking polyurethane foam sandwich panels. Purpose-made 316 L stainless steel heat exchangers suspended in the heat accumulator are used for generation of domestic hot water.

Water is heated using single or multiple heat sources such as solar collectors and heat pumps and the heating water is stored at atmospheric pressure in a closed loop. Potable DHW at regulated mains pressure passes through purpose designed 316 L stainless steel heat exchanger coils suspended within the tank. Energy is transferred from the stored body of water to the potable water inside the heat exchanger coils and made available for distribution. The buffer tank size and the number of heat exchanger coils are selected depending on the DHW flow rate required.

Product details


3500 to 17500 L


Chromadek sandwich panels with EPD rubber lining


60 mm PU with density 43 kg/m3 R-value > 2,65

Heat exchanger

SS 316, wall thickness 0,3 mm and dia 25 or 32 mm. Multiple coils depending on required DHW flow

Pressure rating

Atmospheric for heating water, 10 or 16 bar for DHW

Energycal LSQ with Thermocube

The Thermocube heat accumulator pairs optimally with the a or a bank of   Energycal LSQ heatpumps to provide a safe, scalable and cost effective solution for instantaneous hot water production for a diverse range of applications. Learn more about the LSQ heat pumps.