ModuSat SPDC interface unit

ModuSat® Single Plate Double Circuit HIU

  • Indirect high efficiency heating
  • Suitable for Radiator and Underfloor Heating systems
  • Independent fast recovery Domestic Hot Water (DHW) via a suitable external storage tank fed by the unit (Not Evinox Supply)
  • Compact and wall mounted to fit perfectly in a utility room or kitchen cupboard
  • Control of two output temperatures
  • Flexible installation options with separate HIU and tank
  • Ideal for high-end apartments due to the back-up stored water
  • Suited to student halls of residents with clusters of accommodation

Contact us

Contact us on 01372 722277 for further information or a quotation.

ModuSat® Single Plate Double Circuit (SPDC) Heating Interface Units

Our ModuSat SPDC range of HIUs provide indirect high efficiency heating and independent fast recovery hot water via an externally mounted DHW tank fed by the unit.

Units are suitable for both radiator and underfloor heating systems and are well suited to high end apartments and student halls of residence due to the high capacities and back-up stored hot water.

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Control of Two Output Temperatures

ModuSat® SP DC units are able to control two output temperatures, one for the Heating system and another for the Domestic Hot Water tank, a real benefit for Underfloor heating systems.

When in Domestic Hot Water mode, our Smart Connected Control technology in the ModuSat unit will modulate the primary flow ‘up’ to increase output temperature for fast cylinder recovery, but when in heating mode the primary flow will modulate ‘down’ to reduce secondary output temperature.

This is particularly beneficial for Under Floor Heating systems where there is a requirement for lower temperatures and means there is no requirement for a mixing valve or pump set prior to the heating manifold, saving time and money installing additional equipment.

Smart Energy Regulation and Control

Our Smart Energy Regulation and Control provides a myriad of benefits in terms of HIU performance and optimisation of heat network efficiency. So how does it work?

  • Pressure Independent Control Valves (PICV’s) provide integrated differential pressure control, providing balanced, self-configuring flow through the HIU
  • Fast acting, electronically regulated actuators provide immediate response to changes in energy demand
  • Proportional Integral Derivative (PID) control logic provides accurate actuator/valve control and fast response to hot water demand, without “overshoot” (Reduces energy wastage)
  • Electronically actuated PICV’s also function as a shut off valve, so ModuSat® Smart HIU’s can easily be configured for either credit or PAYG billing systems
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Metering and Billing Ready

The Heat Network (Metering & Billing) Regulations (2014) require each resident to be billed individually for the proportion of the total heat they consume from the heat network.

Our ModuSat® units make this easy, featuring an integrated ultrasonic heat meter, which is MID approved with class 2 accuracy (BS EN 1434), ready to connect to a communication network for metering and billing purposes.

In addition, our PaySmart® pre-payment technology is also integrated into each ModuSat® heat interface unit as standard, and – unlike many other pre-payment billing solutions – can easily be activated remotely at any time and requires no additional hardware or infrastructure to set up.

Technical details

ModuSat® Single Plate Double Circuit Heating Interface Units

The Evinox ModuSat® single plate double circuit heat interface unit (HIU) provides high efficiency heating and independent fast recovery hot water, designed for installation with a suitable external DHW storage tank fed by the unit (not Evinox supply).

The unit consists of a single plate heat exchanger, combined with electronic PID control using Pressure Independent Control Valve (PICV) with modulating actuator achieving a low primary return temperature as well as providing differential pressure control and flow rate regulation.

The SPDC heat interface unit uses a diverter valve to switch secondary flow either through the heating circuit or fed to the external DHW tank and operates in DHW priority mode to provide fast recovery of hot water.

In addition to this the ModuSat® can provide direct control of underfloor heating output temperature without the need for any underfloor pumps, blending valves or mixing valves.

Available in a range of plate sizes and connection configurations, the SPDC HIU is suitable for many different type of installation.


The ModuSat® SP DC unit is designed to operate with Evinox SmartTalk® two-way communication system for remote metering and diagnostics.


The heating circuit consists of a plate heat exchanger (PHE), PICV, safety relief valve, manometer, flow and return temperature sensors, Wilo PWM circulation pump and expansion vessel. The heating circuit flow temperature is controlled by the modulation of the primary flow rate with the integrated PICV actuator. Weather compensation is applied to the set heating temperature using SmartTalk® 2-way communication. Suitable for radiators, underfloor heating or fan coil units.

Domestic Hot Water

Domestic hot water is generated in an external unvented cylinder.

Features & Benefits

  • Very compact design with minimum space required for installation
  • Ultrasonic heat meter MID approved and class 2 accuracy (BS EN 1434)
  • Excellent thermal efficiency achieved using the latest technology and efficient brazed stainless steel PHE’s
  • Integrated PaySmart® technology ready for prepayment billing upgrade (activated remotely at any time)
  • Billing app for use on smartphones and tablets
  • ViewSmart room controller with optional upgrade to provide ENE3 compliant Energy Display Device
  • Electronically controlled PICV for primary flow rate modulation to match demand, differential pressure control and energy shut-off
  • Pipework constructed from copper
  • External filling loop (Optional)
  • SmartTalk two-way communication
  • Remote monitoring, alarms, and diagnostics
  • Wilo PWM Pump – Provides compliance with EU ErP Directive 2015
  • Includes inbuilt TCP/IP technology to operate on an Ethernet network if required
  • Capable of reading an electricity meter (Option for ENE3)
  • Flushing bypass kit enables the primary side of the system to be flushed and cleaned without damage to the unit
  • Motorised diverter valve – to switch between heating & hot water modes
  • Control & monitoring of external tank temperature via loose supplied sensor connected to the ModuSat board

Download the Data Sheet

ModuSat SPDC Data Sheet

ModuSat SPDC Data Sheet

Download the ModuSat® Heat Interface Unit Brochure for More information

Discover how Evinox Energy can deliver the best heating solution for your next new build or refurbishment heat interface unit project

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Heat Networks

  • District and Communal Heat Networks
  • Delivery of low carbon heating
  • Heat Interface Units
  • Energy Metering and Billing
  • Service and Maintenance
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Energy Metering & Billing

  • Credit Billing Services
  • PaySmart® Pre-payment System
  • Billing Solutions for Non Evinox Equipment
  • Heat Network (Metering & Billing) Regulations 2014 Advice and Guidance
  • Domestic Heat Meters and Point of Entry & Bulk Meters
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Service & Maintenance

  • Heat Interface Unit Service & Maintenance
  • Plant Room – Planned Preventative Maintenance (PPM)
  • ModuSat® Heat Interface Unit Enhanced Warranty Cover
  • Combined Packages for Metering, Billing and Service & Maintenance
  • Domestic Boiler Service & Maintenance