Why Refurbish your AHU?

Access and Site limitations

Not all existing AHU plant is installed with future replacement taken into account. This can be particularly problematic in built up areas. The strip out and installation of new units may not be feasible due to the removal of external walls or roofs, road closures for cranes, ceiling, room or basement mounted units etc..

Cost Effectiveness 

As a rule of thumb, the cost of refurbishing an AHU is approx. 35-50% of the cost of buying a brand new model (this is before the cost of removal and installation is included).  It can be more economical to source new components compared to building a new AHU and easier to install saving time and money.

Less Disruption, and more flexibility

Works can be scheduled so as not to interfere with a client’s activities or incur any downtime, affecting production or process in the building. Works can be carried out over weekends or evening, with minimal interference to daily operations.

Refurbishment is often a quicker option from start to finish than replacement. It also gives the choice of separating the necessary works and completing at different times for greater flexibility

Upgrading Existing specification

With such emphasis being put on efficiency, upgrading your existing system can reduce the running cost of your AHU without the need of full unit replacement. Simple upgrades to some of the components can result in reduced operating costs of your AHU:

  • Belt Drive to Plug Fan –This can be achieved with a re-configuration of the fan chamber, and installation of plug fan assembly c/w high efficiency motor
  • Heat recovery – installation of heat recovery into an existing system can off set the heating load on a system utilising the latest development in heat recovery technologies – Run Around Coils
  • Motors upgrades – all motors should be a minimum IE2 or IE3 inverter driven. Any systems still operating stat delta, 2-speed or single speed motors will be operating very inefficiently and can be easily upgraded.
  • If a DX system is installed with R22, this needs to be upgraded to a newer r410a or equivalent.

Increases in airflow, fresh air, heating and cooling demand are common due to the changes in occupancy or use of a building, and sometimes a simple belt and pulley change will not satisfy these requirements.

  • Increase Air flow – installation of larger fan and motor assembly within existing fan chamber
  • Increase in Heating and Cooling demand – Installation of Cooling or heating coil to existing system, or increasing kW output.
  • Change of heating / cooling source – coils can be changed to adapt to the available resources in a building such as:
    • Water – LTHW / CW / MTHW
    • Steam
    • DX



Case study –Dawn Foods, Charleville