Heat Interface Unit

The Hiper HIU is compact and requires very little space and is easy to install. The design meets all varying demands of the home.

It is, in many ways like a combi boiler, providing central heating and instantaneous hot water, but without flame or flue.



Energy efficient

  • Instantaneous hot water production
  • Electronic temperature control
  • Optimised heating temperature control as standard
  • Standby mode temperature control
  • Lower return temperatures to the network
  • Low carbon heat networks - renewable energy sources
  • Weather compensation option
  • Low energy pump
  • Radiators or underfloor heating
  • Minimal maintenance reducing running costs




Description - Hiper Indirect HIU

  • Two plate heat exchangers (PHE) one for heating (CH) and one for hot water (DHWS)
  • The electronics provide 'PROPORTIONAL' reactive control to demand. PID electronic controller
  • Integral PICV (Pressure Independent Control Valve)
  • Maximum efficiency with lowest return temperatures
  • back into the network.
  • Safety with high temperature limits enforced even
  • without an electricity supply
  • Systems can be designed with little requirement for
  • expensive commissioning.
  • Simple to maintain, the plate heat exchangers can be
  • accessed and removed in just minutes.
  • Insulated with a tamperproof steel casing.
  • Plate Heat Exchangers access from the front
  • Wilo low energy pump, fixed or variable speed
  • Automatic air vent
  • 3 bar safety relief valve on the secondary heating side
  • 3 drain points
  • Large surface area strainer mesh for extended maintenance
  • schedules
  • Sealed system heating
  • Thermostatic high temperature protection
  • Flat face union, 3/4" connections




heat interface unit
heat interface unit inner
hiu internal schematic
hiu technical specification