Tml XPCSS02000R Combined heat storage tank Kombinox lt. 2000 in AISI 316L stainless steel with two fixed rigid insulation coils

Combined Thermal Storage Tank Kombinox-SS 1950 Litres – Heating Buffer + Internal DHW Tank 340 L – XPCSS02000R

The XPCSS02000R is a "tank in tank" combined thermal storage system with a capacity of 1950 litres (total puffer volume), designed by TML Industrie Loddo for multi-energy installations with integrated domestic hot water production. The external carbon steel buffer stores heat from continuous and intermittent sources (solar thermal, biomass boiler, backup boiler, heat pump, heat generator), while the internal DHW tank of 340 litres in AISI 316L stainless steel (1.4404) ensures safe, hygienic hot water production. The system is configured with 2 spiral coil heat exchangers in puffer (lower + upper).

Full Technical Specifications – XPCSS02000R

• External buffer (heating storage):
• Material: Carbon steel S235Jr – bare inside – anti-rust coating outside
• Max pressure / Max temperature: 3 bar / 95°C
• Buffer capacity: 1950 litres
• Internal DHW tank (tank in tank):
• Material: AISI 316L stainless steel (1.4404) – Pickling and passivation inside and out
• Max pressure / Max temperature: 10 bar / 95°C
• DHW capacity: 340 litres
• Cathodic protection: Replaceable magnesium anode
• DHW available at 45°C (buffer at 65°C mean, 20 L/min flow): 541 litres
• Lower puffer heat exchanger: Fixed spiral coil 4.8 m² – raw carbon steel – max 10 bar / 95°C
• Upper puffer heat exchanger: Fixed spiral coil 3.8 m² – raw carbon steel – max 10 bar / 95°C
• Insulation: rigid PU foam + PVC 100 mm (B3 DIN 4102)
• ErP: Class C – Heat loss: 144.7 W
• Dimensions (insulated body): Ø 1100 mm × Height 2380 mm
• External diameter (insulation): Ø 1300/1360 mm
• Tilt diagonal R: 2440 mm
• Indicative weight (PCSS/XPCSS version): ~325 kg
• Electric heater connection: 1½" fitting (not included)
• Warranty: 5 years

Operating Principle – Tank in Tank Technology

The Kombinox-SS system uses the "tank in tank" principle: the DHW tank is physically immersed inside the buffer, using the heating circuit water volume itself as the heat exchange medium for DHW production. This approach provides an extremely large heat exchange surface and rapid heating times, while maintaining complete separation between the heating circuit (closed loop, technical water) and the domestic water (open loop). The heat transfer fluid in the buffer and primary heat exchangers must operate in a closed loop to prevent corrosion.

Multi-Energy Compatibility and Applications

The XPCSS02000R is designed to simultaneously integrate multiple heat sources: solar thermal collectors (upper heat exchanger, where fitted), biomass boiler (dedicated flow/return connections), gas or oil backup boiler, heat generator at high temperature, and heating system at high and low temperature (underfloor, fan coils). The large 1950-litre capacity provides adequate thermal storage for large residential buildings, villas, multi-apartment buildings and commercial premises.

Standards and Certifications

The XPCSS02000R complies with: PED Directive 2014/68/EU (Art. 4 Par. 3), Italian D.M. 6 April 2004 N.174, ErP Directive 2009/125/EC.