Achieved Energy Reduction Savings of 95%

The Client

Award winning CFH Docmail Ltd are a forward-looking, green-minded, £46m company specialising in print and post. They are the largest provider of hybrid mail in the UK with our Docmail service allowing users to send real post direct from PC desktops. CFH Docmail are also the third largest postal delivery company in the UK with their own Velopost “fossil fuel free” postal delivery to the doorstep in Bath and Bristol.


The primary objective was to create an energy efficient cooling solution for CFH Docmail’s server room.

  • Design, supply and install an energy efficient cooling system
  • Ensure adequate filtration for fresh air cooling solution
  • Guarantee maximum cooling temperature of 21 degrees throughout the server room


Evaporative Cooling systems are extremely efficient – delivering 35kW of cooling power and only using 2.4kW of electricity with a running cost of 25p an hour. The technology is an outstanding cooling solution for any energy conscious organisation.

  • Installation of one roof mounted Evaporative Cooler Large Eco Cooler Wet Box which has a maximum side discharge flow rate of 10,800 cum/hr at 52Pa
  • As part of the evaporative cooling system, EU4 filtration cartridges incorporated inside the server room
  • An EU4 pre-filter wrap around jacket fitted to the Eco Cooler wet box externally
  • Evaporative cooling has no refrigerants and is a completely natural cooling process
How Evaporative Cooling Systems Work: General Principals
  • Low energy variable speed EC (Electronically Commutated) fans are specified to supply and extract air.
  • Fresh air is brought into the system through EU4 pre-filters and Munters CELdek® pads.
  • Evaporative cooling operates during warm periods to cool air.
  • During winter periods, warm exhaust air is mixed with cold fresh air. This mixing process is described as attemperation.
  • Patented control systems measure and control air flow rate, supply and exhaust temperature.
  • Control systems automatically match air flow to the amount of cooling required.

This is achieved by using the evaporative cooling system in ventilation mode only, therefore with no adiabatic cooling (water wetting the pads) which allows the zone to be controlled for c.50% of the year to maximise energy efficiency.


This is when the evaporative cooling system is operating with the wetting of the pads to control the air conditions to the desired conditions.


This stage enables the modulating dampers, which are controlled via the PLC, to be opened at varying degrees as required and the air from the zone is recirculated with fresh air introduced to maintain air quality as required. This method reuses the heat in the zone and the heat being generated in the zone to maintain the required room temperature where possible.

HEATING (Optional)

If required, the system can be designed to provide a heating solution for when the room drops below a set temperature point.


  • Achieved energy reduction savings of 95%
  • Evaporative cooling is a natural, cost effective and environmentally friendly alternative to traditional air conditioning.

Benefits include:

  • No refrigerants, completely natural cooling process
  • Low running and maintenance costs
  • Low carbon and energy use
  • Exploits the maximum amount of free cooling available


Our case study on SMARTech Cooling’s work with CFH Docmail tells the story of how we helped reduce their energy consumption. If you would like to reduce energy waste, boost profits and cut carbon emissions then contact SMARTech Cooling today.

Let SMARTech Heating & Cooling define and design the right solution for you

As a Carbon Trust Accredited Supplier, we can also help most business access a 10% capital grant (up to a limit of £5,000) towards the cost of energy saving projects.