Filtration for the Removal of Suspended Solids from Industrial Cooling Water and HVAC Water

Water is a significant aspect of a HVAC system (Heating, Ventilation and Air Conditioning). Industrial facilities, large office complexes, hospitals, food and chemical plants all use water as a cooling medium. The cooling water must be effectively filtered to remove suspended solids and other contaminants to:

  • protect the HVAC equipment,
  • maximize heat transfer efficiency, and
  • minimize energy and water consumption.

The basic components of the HVAC system include the following:

  • Compressor (Intercoolers)
  • Condenser
  • Chiller (Evaporator)
  • Cooling Tower
  • Heat Exchangers

There are several sources for the cooling water, including:

  • Cooling Tower
  • Surface Water (River, Lake, Reservoir) and Well Water
  • City Water and Recycled Water

All cooling water requires filtration! Cooling tower water, recycled water and surface water supplies can be contaminated by airborne debris, silt, sand, pollen, algae, and other suspended solids. All these water sources can also be contaminated with pipe scale and corrosion by-products. As the contaminants circulate through the system and deposit on the heat transfer surfaces of compressors, chillers, condensers and heat exchangers, they cause a reduction in heat transfer efficiency and increased pressure losses. When you lose heat transfer efficiency and increase pressure drop, then you need to pump more cooling water to realize the same cooling. The net effect of contamination is increased energy and water consumption.

Filtration of process cooling water is often overlooked; but cleanliness of the cooling water can have significant impact on productivity and profitability of an entire operation, as well as the comfort of employees, patients, visitors, etc. Fouled piping and heat exchange surfaces can result in:

  • Higher Energy Costs
  • Lower Productivity
  • Increased Chemical Costs
  • Higher Water Usage, and
  • Increased Equipment and Infrastructure Maintenance.

Zero Gravity Filters offers three extremely unique and effective separation / filtration technologies to meet your HVAC needs.

  • Maggie – Maggie is a fully automatic, in-line, high intensity, high efficiency, self-cleaning, patented magnetic separator.  Maggie is the best available technology for separating magnetic contaminants from cooling water.
  • Spring Filter – The ZGF Spring Filter is a 316 stainless-steel coil wound with a variable pitch that allows the filter element to open evenly from top to bottom ensuring that all contaminants are completely removed from the filter element with each backwash.  The “nidges” provide an absolute gap to ensure consistent and reliable particle capture. The Spring Filter element is utilized in the EZ Clean family of automatic filtration systems.
  • Tornado – The Tornado is high “G”-force, centrifugal separator.  The Tornado is a simple but extremely innovative device.  The Tornado has no moving parts and no media.  Tornado effectively removes particles without any regular maintenance.

With diminishing maintenance staffs and tighter profit margins, contamination control must be effective, consistent and reliable. 

The selected filtration technology must be:

  • capable of removing small contaminants without negatively impacting the process fluid,
  • automatic to minimize operator involvement
  • relatively maintenance free      

ZGF Maggie, Spring Filter and Tornado technologies satisfy the criteria, and effectively and efficiently capture and remove the contaminants from the cooling / process water. 

ZGF technology can be installed in a variety of processes and applications.

To get a better understanding on where ZGF technology can provide value in operations requiring cooling water, click on one or more of the Process Diagram links below.  The process diagrams show you where a ZGF technology can be implemented in a specific process and the benefits it provides.


ZGF Maggie, Spring Filter & Tornado technologies meet all purchasing and performance criteria by effectively and efficiently capturing and removing the contaminants from the process / cooling water.

ZGF technology will provide value because it is:

  • fully automatic
  • consistent & reliable
  • non-disposable
  • energy efficient - utilizing a minimal amount of electricity and air during purge/backwash
  • able to remove ferrous particles down to 1 micron and non-ferrous particles down to 20 micron
  • environmentally responsible – does not generate additional waste, unlike bags, cartridges and roll media

The product data sheets provide a detailed description and comprehensive overview of each product technology. If you want to learn more about ZGF EZ Clean, Maggie or Tornado technology, then click on one of the links to download the:

Seeing is believing!

Some people need to see something in operation to really get it.  Click on the links below to see how each technology works.

  • Spring Filter animation – The animation shows the basic principle of operation.
  • Spring Filter video - See the coil open and shimmer and the contaminants disappear!
  • Phoenix animation – The animation shows the basic principle of operation.
  • Phoenix video - The narrated video explains and allows you to see how the Phoenix works; and you can see how all debris is removed during backwash when the Spring Filter opens and shimmers
  • Maggie and Smart Drum animation – The animation shows the basic principle of operation.
  • Maggie video – The video shows and explains how the Maggie technology works. See how Maggie captures ferrous contaminants and then purges them to the Smart Drum!
  • Tornado animation – View the Tornado in operation.

ZGF technology provides value

To learn more about how filtration impacts the cost of process cooling equipment and infrastructure, click on the Powerpoint presentation - Impact of Filtration on Process Cooling Water Systems.

Click on Success Stories to jump to the Success Stories / Case Studies page to learn how ZGF technology provides value.  Click on the links below to learn how our customers were able to reduce operating costs, improve process reliability and quality, and reduce the environmental footprint of their operations by implementing ZGF technology.


Simplicity, consistency, reliability and the lowest cost of ownership make ZGF technology the best solution and value for all your filtration needs!

ZGF is your preferred partner.

 Filtration should not be a burden.

 Filtration should be a tool that improves quality and reduces cost.

Let us help you meet your objectives and make your job easier!


 ZGF has the experience and dedication to customer satisfaction that you are looking for. Contact us or request a quote today.