Heat Recovery, Pumps & Renewables

Heat Recovery and Heat Pump units both capture and/or convert naturally occurring energy and use this as a power source for either your building's ventilation, heating or hot water.

Both are proven renewable technologies and have been used throughout the heating and cooling industry for decades. Recent advances have made them ideal for both commercial and domestic use. Both can greatly reduce CO² emissions and energy costs.

Our heat recovery units are designed to save energy and improve indoor air quality by recovering heat from the transfer of warm air to cold air via exchangers. Similarly, our air source heat pumps are designed to provide hot water to either traditional radiators or under floor heating systems by converting outdoor air to heat energy.

Heat Pumps and Renewables



Duplexvent unitAn effective building ventilation solution has become critical in recent years as a result of increased levels of insulation and air tightness in residential and commercial buildings. Factors such as ever increasing energy costs, modern construction methods and building regulations have ultimately led to poor indoor climates that can cause health problems for occupants and damaging long term effects to the fabric of a building.

Our Duplexvent commercial heat recovery units are designed to save your business energy and improve the indoor air quality. These units provide ventilation and heat recovery (for commercial and industrial areas) by using polypropylene exchangers which recover heat from the transfer of warm air to cold air via exchangers with high conductivity and performance.


Heat Recovery diagramHeat recovery technology works by a process of continuously preheating an incoming cool supply air by warming it with the outgoing exhaust air. Warm air is not simply exhausted through the open window but transfers most of its heat to the supply air in a highly efficient heat recovery exchanger before being exhausted (at no time do the airstreams mix as the heat radiates through the plates of the exchanger).

Fresh air is fed directly from the outside into the ventilation system through a filter. The heat taken from the extracted air is used to warm the fresh filtered air in the exchanger and then flows through ducting. By undercutting doors and fitting transfer grilles, fresh air circulation is ensured throughout the dwelling.

In Practice

Stale air, contaminated with humidity, toxins and smells is extracted via outlet grilles from the kitchen, bathroom and toilet areas. These outlet grilles in toilets and wet room areas, such as the bathroom, en-suite, utility and kitchen allow a constant or demand oriented air flow volume to be extracted.


  • Saves energy by reducing heating costs
  • Extracts airborne pollutants that can cause allergies and asthma
  • Constantly refreshes the internal atmosphere
  • Removes condensation and humidity
  • Supplies warmed, filtered air to living and working spaces
  • Up to 94% heat recovery
  • SAP Appendix Q eligible models
  • Helps reduce a buildings carbon footprint
  • Meets building regulations, Approved document F, April 2010 (MVHR)

BREEAM (BRE Environmental Assessment Method)

Our heat recovery units help the building they are installed in to be assessed for the BREEAM standard (BRE Environmental Assessment Method) - the leading and most widely used environmental assessment method for new buildings. By setting the standard for best practice in sustainable design, BREEAM has become the de facto measure used to describe a building's environmental performance.




Ecodan W85 unitAir source heat pumps are different to ground source pumps and have a much smaller physical footprint. This makes them easier to install and therefore more suitable for a wide variety of properties from flats to detached houses.

The heat pump system consists of an external box which is fitted to your outside wall. It harvests renewable, low grade energy from the outside air and upgrades this into useful heat to supply a home with hot water and heating. For every 1kW of electricity fed into an external heat pump unit, you could get at least 3kW of heating energy (depending on your current heating system, satisfactory system design & installation and how you use the heating system).


Heat pump technology works by using a vapour compression cycle very similar to a refridgerator. Refrigerant in the unit's evaporator is colder than the external source causing heat to move from the outside air into the refrigerant, which then evaporates. This vapour is then driven to the compressor where it reaches a higher temperature and pressure. This heated, pressurised vapour then enters the condenser and releases heat energy as it condenses.The refrigerant then moves to the expansion valve, dropping in temperature and pressure and returns to the evaporator, completing the cycle.

In Practice

Ecodan Energy SavingThe new advanced control system of our Ecodan unit provides an optimum variable flow temperature control designed to supply traditional radiators with hot water.

Whereas the capacity control in traditonal boiler-fed radiator systems (with fixed flow temperature) is controlled by the on/off operation of thermostatic radiator valves (TRV), the Ecodan unit varies the flow temperature automatically (based on the ambient temperature) to keep the house warm. This means that the TRV's don't have to be turned on and off to maintain the desired comfort level.

By operating at much lower flow temperatures, the Ecodan system can significantly improve overall system efficiency, achieve energy savings of over 30% (even greater for under floor heating systems) and achieve better comfort levels through a more consistent heat output.

Heat pump units are designed to work all year round and in temperatures as low as -25ºC.


Our Ecodan range is designed to meet the demands of today’s domestic hot water and heating requirements. It is simple to install, cost effective for the end-user and offers outstanding energy efficiency. This makes the Ecodan heating system an ideal choice for designers, architects, installers.

Benefits of an Ecodan system include:

  • Up to 50% reduction in CO² emissions
  • Helps to achieve Level 3 of the Code for Sustainable Homes
  • Easy to install - the self contained unit only requires water and electric connections
  • No gas supply, flues or ventilation required
  • No need for groundwork or external pumps
  • Single phase power supply with a low starting current
  • 3 phase option available (14kW)
  • Low maintenance
  • Even higher savings and CO² reductions for homes with underfloor heating systems*
  • Designed for domestic use
  • Low noise - market leading 45dBA at 1 metre**
  • Reduced VAT to 5% for domestic applications
  • *Assuming the design flow temperature is 35ºC maximum

    **Based on a 5kW model

    Whole House Solutions

    Whole house solutionThinking of installing a heat pump? Why not consider a 'whole house solution' and install solar PV panels?

    Our heat pump and solar PV solutions can be used to create a whole house solution - reducing the need for conventional energy sources like mains gas and electricity.





    Variable Flow Heating

    Hot Water

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