Safe. Easy to install. Energy efficient.

In response to increasing customer demand, we have recently launched a new Heat Interface Unit, the Hi-Max Instant ID. The Hi-Max Instant ID is designed to provide both central heating and domestic hot water to dwellings which are served by either a district heating scheme or a centralised boiler system.

Comprising two plate heat exchangers - one for the hot water, and one for the apartment heating system - the Hi-Max Instant ID is designed to ensure that the primary return temperatures going back to the district heating system are low, helping the central zero or low carbon technology to operate highly efficiently.

  • Features and benefits
  • Specification
  • Download brochures and manuals
  • BIM
HI Max Instant ID
  • Compact design, can fit in a standard kitchen cupboard
  • No need for boiler flues and no annual gas safe service required
  • Suitable for single and dual zone heating systems
  • Fully modulating pressure independent flow control technology for automatic balancing and fine temperature control
  • Pulsed bypass pre-heat function to improve the response time to demand
  • Scale reducing feature taking heat away from the hot water plate heat exchanger when there is no hot water demand
  • DHW and central heating plate heat exchangers provide a pressure break to both systems
  • 8 Litre central heating expansion vessel 
  • Access to all components for ease of maintenance
  • Plug and play approach to commissioning
  • Provision for a heat meter of your choice - spool piece fitted - 3/4" BSP x 110mm
  • Automatic fault diagnostics


Order Code 

Heatrae Sadia Hi-Max Instant ID-5/60 HIU 


Heatrae Sadia Hi-Max Instant ID-5/80 HIU


Heatrae Sadia Hi-Max Instant ID HIU Casing


Heatrae Sadia Hi-Max Instant ID HIU Standard First Fix Rail


Heatrae Sadia Hi-Max Instant ID HIU Basic Stand-off Kit


There are currently no BIM files for this product

Approved and accredited

Related information

Our factory compliance standards

Engineered in Britain.

Trusted worldwide.