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NIMBUS: Buildings + Water = Technology

Updated: Jul 5

Let’s talk about the value of water, inherent threats and technological innovation

HVAC began with water – air sent through water-cooled coils. Water is essential to many things in our world, including us. But with water comes demand risks and threats, like bacteria.

If you own a building, you are likely familiar with the word Legionella – which causes Legionnaires Disease. If you have cooling towers, you likewise are no stranger to regular maintenance to remove scale, contaminants and other inhibitors that may corrode the tank, limit water flow and even cause your equipment a premature end due to strain on the system if water is not properly maintained.

With challenges come the opportunity for innovation with advancements in technology and great minds determined to solve the problem at hand. And problems evolve. Today we face water scarcity due to large scale consumption. Energy costs and conservation is needed to protect resources and the environment, along with business margins and the consumer purview. Disease generates liability which in turn drives legislative measures to take action and develop industry standards.

Enter NIMBUS® Advanced Process Cooling. NIMBUS engineers, designs, and manufactures VIRGA X3™ and VIRGA III® hybrid adiabatic cooling systems. Hybrid adiabatic cooling technology was developed in Europe as a response to widespread regulations aimed at preventing the spread of Legionnaires' disease by replacing traditional evaporative cooling systems, one of the most common breeding grounds for Legionella.

VIRGA systems by NIMBUS eliminate standing water in favor of a fully closed coolant path, and the intermittent use of fresh water to augment the system's cooling capacity only on the hottest days of the year by releasing a fine water spray into the air prior to the air being pulled over the copper cooling tubes – lowering the air temperature and increasing the heat rejection capacity of the unit.

The control system cycles individual fans as process water temperature dictates or uses VFD’s or ECM for fan cycling, and ultimately activates the fine spray of water when required. During the colder months, water spray activation is not required and the unit operates as a dry air cooler — eliminating sump freezing and dangerous ice buildup common with traditional fluid coolers.

Hybrid adiabatic cooling technology has yielded significantly lower operating costs compared to traditional cooling technology and has lower the risks to the public health and the environment. NIMBUS custom manufactures VIRGA systems in the heart of Alabama, USA.

Advance Your Cooling

VIRGA X3 and VIRGA III systems provide efficient, natural, and sustainable cooling technology for virtually any application. VIRGA systems yield numerous environmental and economic benefits, including:

· Significantly conserves water and drain fees vs. traditional cooling systems

· Virtually eliminates Legionella and bacterial risks

· Reduces chemical use and disposal

· Virtually maintenance-free

· Quick installation

· No water collection pool to clean – ever

· Engineered to last

· Stainless steel and copper construction

· Reduced footprint compared to traditional dry coolers

· Corrosion-Resistant Copper Tubing

Energy Conserving Fans:

The fans cycle on and off in stages as required to maintain the exiting water temperature at a predetermined set point, greatly reducing energy consumption. VFD’s and ECM can be incorporated for fan cycling as an alternative.

Ongoing Benefits:

Save Water, Save Health, Save Energy. Be Blue. VIRGA systems reduce average water consumption up to 95% in some applications and eliminate the primary breeding ground for the bacteria which leads to no fewer than 50,000 cases of Legionnaires' disease annually. The fans on VIRGA systems are programmed to cycle on and off in stages. EC fans and AC fans (with or without VFD) are offered. VIRGA systems feature stainless steel construction and copper coils provide longevity, and a reduced footprint saves the space a conventional dry-air cooler would consume. Since the VIRGA hybrid adiabatic cooling systems do not require a reservoir of standing water to cool, the costly maintenance and dangerous sump freezing associated with traditional fluid coolers are eliminated.

Talk to a Boland professional to learn more about emerging HVAC technology:


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