Nexus Dual Stage

NEXUS DUAL STAGE units are designed specifically for applications where the hot water loading is high. Units with instantaneous heat transfer of up to 150kW for HWS generation are available. A state of the art arrangement of multiple heat exchangers combined with accurate digital temperature control, ensures that domestic hot water can be delivered across a wide range of demand volumes.

Units with nominal HWS heat transfer capability of 75, 100, 125, & 150kW are available. All units have a nominal heat transfer of up to 25kW for central heating.



  • Automatic balancing control
  • Central heating Pump, 10 Ltr expansion vessel and 4 bar safety valve
  • Ultrasonic Heat Meter – MID Class 2, RHI Compliant
  • White painted casing with hinged, lockable door
  • Digital HWS temperature control
  • Domestic hot water delivery flow rate down to as low as 2 l/min
  • Up to 25kW Central Heating output options
  • Integral filling point, pressure gauge and auto air vent
Domestic hot water heat transfer 150kW
Heat exchanger materialAISI 316 stainless steel
Heat exchange capacity150 kW
Primary Circuit
Primary temperatures80°C/38°C
Flow rate0.864 l/s
Secondary Circuit
Secondary temperatures10/60°C
Flow rate0.714 l/s
Central heating heat transfer 20kW
Heat exchanger materialAISI 316 stainless steel
Heat exchange capacity20 kW
Primary Circuit
Primary temperatures80/64°C
Nominal primary flow rates0.3 l/s
Secondary Circuit
Secondary temperatures45/75 °C
Nominal secondary flow rate (max)0.16 l/s
Weight60kg (Nominal)


  • Heat meters with optional Mbus, Pulse In/Out or RF output for remote reading or Pre-payment facilities
  • Adjustable heating temperature – For underfloor heating systems
  • HWS recirculation system
  • Plumbing Jig, Flushing bypass, Isolation valves
  • Buffer vessels (VISTRON BXL and VISTRON B)
  • Low loss headers
  • Water meters (For external fitting)