What is an adiabatic cooler?

They work in much the same way as a dry air cooler for the majority of the year, but they also come fitted with a mains cold water adiabatic spray bar system that is the final stage of cooling. This is only activated during the warmer times of the year, whereby it emits a mist of water that evaporates into the air stream and can reduce the air on temperature to the heat exchange coils by up to 12°C lower than the dry bulb ambient temperature during typical UK summer conditions.

For example, if the summer temperature within your location reaches a maximum of 35°C, the adiabatic cooler will be able to reduce the air on temperature to 23°C and maintain 26°C fluid to your process.

When is an adiabatic cooler considered the most suitable product for cooling?

Generally, when you require lower temperatures to what a standard dry air cooler can provide, but not as low as when a chiller becomes the preferred option.

Adiabatic coolers are able to achieve as low as anywhere between 23-26°C cooling fluid supply temperature depending on where your site is within the UK.

Another good use for adiabatic coolers is when a dry air cooler footprint is too large for the available space on site. By using an adiabatic cooler at the increased process fluid supply temperatures that a dry air cooler is generally used for, you can decrease the footprint of the unit and ensure that you still maintain the cooling duty and temperature requirements that you need.

What is a free cooler?

A free cooler is in effect a dry air cooler and therefore operates and cools the process fluid in exactly the same way as described above.

Where they differ is that they are used as a complementary product with a chiller.

How does a free cooler work in conjunction with a chiller?

Free coolers utilise the external ambient temperature to reduce the need for using a chiller on a process cooling application.

This saves energy and improves the carbon footprint of your chilled water system.

When ambient air temperatures are below the water return temperature, the free cooler can start to provide partial free cooling and depending upon how efficient it is sized, it can provide 100% free cooling in ambient air temperatures of just 3°C below the water supply temperature.

Depending upon your process temperature requirements, this can typically ensure that your chiller is partially or fully offloaded for up to 90% of the year. This has the added advantage of ensuring that your chiller is not overstressed and only takes over the full cooling requirements at the hottest times of the year, improving the system resilience and the lifespan of your chiller.

When should a free cooler be considered?

Whenever you have a need for all year round cooling, which will be a requirement for nearly all process cooling applications and when your process fluid temperatures are around 10-15°C higher than your minimum ambient temperatures, we can normally design a free cooler to give sufficient energy savings to make it a worthwhile investment, especially if you are running 24 hours a day.

Please contact us and we can fully assess your application and offer a free cooler solution with full technical data, running costs and Return of Investment (ROI) calculations.

What is a cooling tower?

A cooling tower is a product that cools the process fluid either directly (open circuit), or indirectly (closed circuit). They also have fans that are induced draft design (fans on the air outlet side of the unit) or forced draft (air on the air inlet side of the unit).

Our most common cooling tower solutions are induced draft open circuit and so for the purposes of explaining how a cooling tower works, we will use this type of product as the basis.

Warm water from the process is returned to a water distribution system at the top of the tower. The water is distributed over the wet deck fill pack by means of large opening nozzles. Simultaneously, air is drawn in through the air inlet louvers at the base of the tower and travels upward through the wet deck fill opposite to the water flow. A small portion of the water is evaporated which removes the heat from the remaining water. The warm moist air is drawn to the top of the cooling tower by the fan and discharged to the atmosphere. The cooled water drains to the basin at the bottom of the tower and is then pumped back to the process.

As an example, our induced draft open circuit cooling towers can achieve a fluid temperature that is only 3°C above the wet bulb ambient temperature. If the summer temperature within your location reaches a maximum of 35°C dry bulb / 22°C wet bulb, the unit will be able to maintain 25°C fluid to your process.

When is a cooling tower considered the most suitable product for cooling?

Generally, when you require lower temperatures and / or reduced overall cooling plant footprints due to space limitations on site to what a standard dry air cooler or adiabatic cooler can achieve.

Cooling towers are able to achieve as low as anywhere between 21-25°C cooling fluid supply temperature depending on where your site is within the UK.

As the range is very large with multiple options and solutions to suit specific site applications / locations and can be applied to 100,000kW+ cooling applications, please let us know what your requirements are and we can design the most suitable solution to suit.

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