Evaporative Condensers

ATC-DC Evaporative Condenser

ATC-DC Evaporative Condenser

The ATC-DC is an induced draft, counterflow design evaporative condenser. Standard construction includes the patented, high efficiency EVAPCO Ellipti-fin Coil, EVAPCO’s new ARID fin Pak™ dry coil, and Z-725 galvanized steel casing and basin. Type 304 or 316 stainless steel construction is available for the basin or the entire unit.

Independently certified to withstand seismic and wind load forces at ALL Building locations in North America.

The ATC-DC line of evaporative condensers represents EVAPCO’s newest advancement in thermal heat transfer research and development. Utilizing the NEW ARID finPak™ heat transfer coil, the ATC-DC offers improved heat transfer during dry operation and significant water savings due to extended periods of dry operation. The ATC-DC is the latest example in EVAPCO’s on-going commitment to quality, environmentally friendly products.

Superior Air Inlet Louver and Screen Design

The air inlet louver screens on the ATC-DC are constructed of corrosion-free PVC. They are a two pass design that minimizes splashout and reduces the potential for algae formation inside the cooler.

In single pass louver systems used by other manufacturers, circulating water droplets tend to splashout, especially when the fans are shut off. With the two pass louver system, the water droplets are captured on the inward sloping pass, minimizing splashout problems.

This unique louver design completely encloses the basin area. Direct sunlight is blocked from the water inside the cooler, thereby reducing the potential of algae formation. Water treatment and maintenance costs are substantially reduced.

While effectively containing the recirculating water and blocking sunlight, the louver design has a low pressure drop. The low pressure drop results in lower fan energy consumption, which reduces the operating costs of the cooler.

Fast, On-Time Shipments

The ATC-DC is completely factory assembled and manufactured by a dedicated professional workforce, expert in building Evaporative Condensers. Factory trained mechanics and EVAPCO's strict quality control and inspection procedures guarantee the quality of every unit shipped.

EVAPCO's controlled factory environment ensures fast on-time shipments, allowing the ATC-DC to be available WHEN THE CUSTOMER WANTS IT!

Ellipti-fin® Cooling Coil

The new ATC-DC Evaporative Condenser utilizes Evapco's patented Ellipti-fin® coil design which assures even greater operating efficiency. The elliptical tube design allows for closer tube spacing, resulting in greater surface area per unit plan area than round-tube coil designs. In addition, the revolutionary Ellipti-fin® design utilizes elliptical spiral fin coil technology which has an inherent air side pressure drop lower than finned round tube designs. This permits greater water loading, making the new Ellipti-fin® coil the most effective design available.

The coils are manufactured from high quality steel tubing following the most stringent quality control procedures. Each circuit is inspected to ensure the material quality and then tested before being assembled into a coil. Finally, the assembled coil is pneumatically tested at 35.5 bar under water to ensure it is leak free.

To protect the coil against corrosion, it is placed in a heavy steel frame and then the entire assembly is dipped in molten zinc (hot-dip galvanized) at a temperature of approximately 420°C.

Efficient Drift Eliminators

The ATC-DC is equipped with an efficient drift eliminator system that effectively reduces entrained water droplets from the air discharge to less than 0.001% of the spray water flow rate.

The eliminators are constructed of non-corrosive PVC with a multi-pass design for maximum drift reduction. They are assembled in modular sections for easy removal and access to the water distribution system.

In addition to reducing drift, the eliminators also function as effective debris screens which protect the spray system from sunlight and debris.


ARID fin Pak™ Dry Cooling Coil

The new ATC-DC Evaporative Condenser utilizes the ARID fin Pak™ Dry Cooling Coil. Installed in the air discharge of the condenser the ARID fin Pak™ dry cooling coil is piped in series with the evaporative cooling coil. The ARID fin Pak™ dry cooling coil is constructed of 304L Stainless Steel tubes and tubular Stainless Steel header with carbon steel coil connections for easy field piping. The fins have fully drawn collars to maintain consistent fin spacing and continuous surface contact over the entire tube to maximize heat transfer. The fins are constructed of Aluminum/Manganese alloy for superior corrosion resistance.

Maintenance Free ZMII® Spray Nozzle

EVAPCO’S Zero Maintenance ZMII® Spray Nozzle remains clog-free while providing even and constant water distribution for reliable, scale-free evaporative cooling under all operating conditions. The heavy duty nylon ZMII® Spray nozzles have a 1-5/16" diameter opening and a 1-1/2" splash plate clearance. Furthermore, the fixed position ZMII® nozzles are mounted in corrosion-free PVC water distribution pipes that have threaded end caps. Together, these elements combine to provide unequaled coil coverage and scale prevention, making it the industry’s best performing non-corrosive, maintenance-free water distribution system.

Technical Data

Unit:    Industrial evaporative condenser

Models:    417 Models (ATC-DC-89G-25-1EF to ATC-DC-2420N-35-2EF)

Width:     2.388 / 2.991 / 3.607 / 4.906 / 6.112 / 7.344 mm

Design:    Induced draft

Capacity:    490 till 5.460 kW

Air Flow:    20,1 till 139,9 m³/s

Fan:    Axial

Drive:    Powerband-belt driven

There are 2 principles of operation:

Evaporative (Wet) Mode - Spray Pump(s) Energized

The refrigerant gas is discharged from the compressor into the inlet of the ARID finPak™ Dry Coil which is positioned in the discharge air stream above the unit’s drift eliminators and below the fan section. Ambient air is drawn into the unit, by the condenser’s fans, through inlet louvers located in the lower section above the water basin. The air is drawn upward through the wet coil into the drift eliminators (which remove entrained water droplets from the air stream) and into the ARID fin Pak ™ Dry Coil Heat from the refrigerant gas is transferred to the air as it comes into contact with the tubes and densely packed fins of the ARID fin Pak ™ Dry Coil. The refrigerant gas exits the ARID fin Pak ™ Dry Coil and travels via inter-connecting piping (by others) to the inlet of the Ellipti–fin® Coil located in the lower section of the ATC-DC Condenser. Water from the condenser’s sump is circulated over the wet coil as the ambient air is simultaneously drawn into the unit and travels up through the Ellipti–fin ® . A portion of the spray water is evaporated into the air stream as it travels through the wet coil. This evaporative process cools the spray water, which in turn cools the coil tubes and extended surface fins. The cool tube walls and extended surface fins cause the refrigerant gas to give up heat and condense into a liquid. The condensed liquid flows out of the Ellipti–fin ® to the high pressure receiver for return to the system. The water which has not evaporated falls into the sump and is recirculated by the spray pump to the water distribution system located above the Ellipti–fin ® .


Dry Mode - Spray Pump De-energized

The refrigerant gas is discharged from the compressor into the inlet of the ARID finPak™ Dry Coil which is positioned in the dry air stream above the unit’s drift eliminators and below the fan section. Ambient air is drawn into the unit by the condenser’s fans, through inlet louvers located in the lower section above the water basin. The air is drawn upward through the Ellipti–fin® into the ARID fin Pak ™ Dry Coil above. Heat from the refrigerant gas is transferred to the air as it comes into contact with the tubes and densely packed fins of the ARID fin Pak ™ Dry Coil. The refrigerant gas exits the ARID fin Pak ™ Dry Coil and travels via the inter-connecting piping to the inlet of the Ellipti–fin ® . The ambient air entering the unit travels upward through the Ellipti~fin Coil which in turn cools the coil tubes and extended surface fins. The cool tube walls and extended surface fins cause the refrigerant gas to give up heat and condense into a liquid. The condensed liquid flows out of the Ellipti–fin ® to the high pressure receiver for return to the system. There is NO WATER consumed during this mode of operation.


Significant water savings

The ARID-fin Pak™ Dry Coil combined with EVAPCO’s Ellipti-fin® coil technology enables the ATC-DC to be operated in a 100% Dry Mode at a significantly higher switchover temperature than that of a typical bare tube coil evaporative condenser. This leads to a much higher number of hours per year the condenser can operate in dry mode (spray pumps off), thus significantly reducing annual water consumption. This combination of heat transfer technologies makes the ATC-DC the most water efficient EVAPCO condenser.

Easy maintenance

The ATC-DC design is optimized for easy access to all critical locations and components. The inlet louvers are removable and provide an easy access to the sump. The complete sump can be cleaned from the outside of the unit. Large access doors provide easy access to the eliminators, spray- and drive system.

Best choice to avoid Legionaires Disease

Maintenance is crucial to avoid the proliferation of the LD-bacteria. Avoidance of the penetration of sunlight to the inner part of the condenser, no stagnant zones in the sump and cleanable spray systems are of equal importance. The ATC-DC condenser is equipped with WST (Water and Sight Tight) inlet louvers to avoid the penetration of sunlight into the sump via the inlet louvers. The high performance eliminators (0.001% drift rate) avoid the penetration of sunlight via the fan-opening onto the spray system and coil. The sump is sloped and drains completely, stagnant zones are not present. The spray system is completely dismountable (including nozzles) and is executed with a removable end-cap for easy cleaning.

Low risk for recirculation

Due to the large distance between the high speed air outlet and the multi-sided low speed air inlet, the risk for recirculation is minimized.

Low energy consumption

The energy consumption of the ATC-DC condenser is minimized due to the optimal heat exchange and the application of axial fans.The heat exchange efficiency of counterflow cooling towers is the highest achievable compared to cross-flow and parallell flow heat exchange. On top of the efficiency advantage, it is generally known that axial fans consume on average more than 50% less motor-power than centrifugal fans. The result is an overall optimized and low engergy consumption.

Designed for easy maintenance, the ATC-DC Evaporative Condenser leads the industry in service friendly features. The three most critical areas for evaporative condenser maintenance are the basin, drive system, and coil. The ATC-DC basin section is designed to allow quick and easy access from outside the cooler. Just like the basin, all service to the drive system can be safely performed from the side of the cooler, and EVAPCO's Power-Band drive system is the easiest belt drive system to maintain in the industry! The exclusive Ellipti–fin™ Technology (Patent Pending) and EVAPCO’s new ARID fin Pak™ dry coil are designed for trouble-free maintenance and long life straight from the factory.

Motor Mount, Power Band Belt Adjustment and Bearing Lubrication - 2.4 m & 4.9 m

The fan motor and drive assembly are designed to allow easy servicing of the motor and adjustment of the belt tension from the exterior of the unit. The T.E.F.C fan motor is mounted on the outside on these models and is protected from the weather by a cover which swings away for maintenance.

A large hinged access door is located on the side of the unit for easy access to the fan drive system. The belt can be adjusted by tightening the J-Bolts on the motor base and the tension can be checked easily through the access door, all while standing at the side of the unit. 

The bearings can also be lubricated from the side of the unit. The bearing lubrication lines have been extended to the exterior casing and are located by the access door, thus making bearing lubrication easy.

Access ladders and working platforms are available as an option to facilitate maintenance.

Motor Mount, Power Band Belt Adjustment and Bearing Lubrication 3 m, 3.6 m, 6.1 m & 7.3 m

The T.E.A.O. fan motor is located inside the fan casing on the large ATC-DC Evaporative Condenser, and is mounted on a rugged heavy duty motor base. The motor base is designed to swing completely to the outside of the unit through a very large, hinged 1,3 square meters access door greatly simplifying motor maintenance.


The unique swinging motor mount designed for these models features easy belt adjustment from the exterior of the unit. The T.E.A.O. fan motor is mounted on an adjustable base which is supported by two heavy duty galvanized steel pipes. The belt is adjusted by tightening an all-thread which runs through the motor base.

The innovative motor base features a unique locking mechanism for a positive belt adjustment and is also used to adjust the belt tension if a wrench is not available.

Bearing lubrication fittings are extended to the side of the unit inside the access door to allow easy application of the bearing lubricant. This external location allows for easy servicing of the bearings and is another important advantage of EVAPCO equipment.

To facilitate motor removal, an optional motor davit is available.

Easy, Removable Air Inlet Louvers with Quick Release Fasteners

The ATC-DC features a Quick Release Fastener design consisting of (2) two large thumbscrews and a latch system. By loosening the thumbscrews, the latch pulls up and out of the louver frame, allowing the louver to be removed while the latch and thumbscrews stay on the evaporative condenser.

Easy Access

The cold water basin section is easily accessible from ground level by simply removing the (2) two Quick Release Fasteners on the inlet louver assemblies surrounding the evaporative condenser and lifting out the lightweight louver.

The basin can be accessed from all (4) four sides of the condenser. This open basin design enables the ATC-DC basin to be easily cleaned.

Clean Pan Design

The ATC-DC features a sloped basin from the upper to lower pan section. This "Clean Pan" design allows the water to be completely drained from the basin. The evaporative codenser water will drain from the upper section to the depressed lower pan section where the dirt and debris can be easily flushed out through the drain. This design helps prevent buildup of sedimentary deposits, biological films and minimizes standing water.

Stainless Steel Strainers

The EVAPCO standard for many years, the stainless steel strainer is one component of the closed circuit cooler subject to excessive wear and corrosion. With stainless steel construction, this component will last the life of the cooler.

IBC Compliant

What is IBC?  

The International Building Code requires that evaporative cooling equipment must meet the same seismic or wind load forces as the building to which they are attached.

How does it apply? 

Based on project zip code and site design factors, calculations are made to determine the equivalent seismic "g force" and wind load on the unit.

What does EVAPCO offer?

* Standard Structural Design

                    -Projects with ≤ 1.0g seismic or 145 psf wind loads

* Upgraded Structural Design

                    -Projects with > 1.0g seismic or 145 psf wind loads

* The upgraded structural design package for the New ATC-DC is designed for 5.12g and 145psf, making it applicable to ALL building locations in North America.

Fan Shaft Bearings

The fan shaft bearings on the ATC-DC Evaporative Condenser are specially selected to provide long life, minimizing costly downtime. They are rated for an L-10 life of 75,000 to 135,000 hours, making them the heaviest duty pillow block bearing in the industry used for Evaporative Condenser duty.

Drive System Sheaves

Drive system sheaves located in the warm, moist atmosphere inside the evaporative condenser are constructed of an aluminum alloy. Those located externally are protected by a hinged cover.

Power-Band Belt Drive

The Power-Band drive is a solid-back multigroove belt system that has high lateral rigidity. The belt is designed for evaporative condenser service, and is constructed of neoprene with polyester cords. The drive belt is sized for 150 percent of the motor nameplate horsepower ensuring long and trouble free operation.

The standard design of the EVAPCO ATC-DC provides the customer with the most efficient and easiest Evaporative Condenser to maintain in the industry. There are additional options which can make maintenance easier, extend the life, or enhance the performance capabilities of the Evaporative Condenser. These options are listed below.

Stainless Steel Water Basin

EVAPCO condensers have a modular design which allows specific areas to be enhanced for increased corrosion protection. The basin area of the condenser experiences turbulent mixing of air and water, in addition to silt build-up. In conjunction with the EVAPCOAT Corrosion Protection System, EVAPCO offers an optional Stainless Steel Welded Basin. This option provides Type 304 or 316 stainless steel for the entire basin area including the support columns of the cooler and the louver frames. The basin section provides structural support for the unit; it is also the part of the unit that is most prone to corrosion. For maximum protection against corrosion, EVAPCO can provide a Stainless Steel Welded Basin as an affordable option.

Working Platform & Ladder with Davit

ATC-DC Condensers are available with a self-supported external working platform and ladder. Two separate platforms will allow easy access to the motor and drive system, water distribution system as well as the ARID-fin Pak™ coil. The working platforms are constructed of the heavy duty galvanized steel. The CE compliant working platform option uses a straight ladder as standard and ships in sections for easy installation.

The optional davit eliminates crane rentals and facilitates the removal of motors and fans. The davit is constructed of aluminum for ease of use. When the davit is ordered, the galvanized steel bracket is mounted on the side of the unit. The Davit ships loose and is installed in the field.

Electric Water Level Control

EVAPCO Evaporative Condensers are available with an optional electric water level control system in place of the standard mechanical makeup valve and float assembly. This package provides very accurate control for the basin water level and does not require field adjustment, even under varying operating conditions.

The control was designed by EVAPCO and is manufactured exclusively for EVAPCO. It consists of multiple heavy duty stainless steel electrodes. These electrodes are mounted external to the unit in a vertical stand pipe. For winter operation, the stand pipe must be wrapped with electric heating cable and insulated to protect it from freezing.

The weather protected slow closing solenoid valve(s) for the makeup water connection is factory supplied and is ready for piping to a water supply with a pressure between 5 and 125 psig (35 kPa and 860 kPa).

Electric Immersion Heaters

Electric immersion heaters are available as an option and are located in the basin of the condenser. They are sized to maintain a 4.4°C pan water temperature at -18°C ambient with the fans off *. They are furnished with a thermostat and low water protection device to cycle the heater on when required and to prevent the heater elements from energizing unless they are completely submerged. All components are enclosed in rugged, weather proof enclosures for outdoor use.

(*) - Electric heater selection based on -18° C ambient temperature. For alternate low ambient heater selections consult the factory

Remote Sump Configuration

For units operating in areas where temperatures may be very low, or where low temperatures may occur during periods when the unit is not 

operating, a sump located inside the building is the preferred means of ensuring that the basin water will not freeze. For these applications, 

the condenser will be supplied without the spray pump, suction strainers and all associated piping, but is furnished with an oversized bottom outlet.






Solutions for Sound Sensitive Applications

The ATC-DC Evaporative Condensers are now available with four (4) equipment options to reduce the overall sound generated from the side or top of the condenser. Each option provides various levels of sound reduction and options can be combined to provide the lowest sound level. Consult EVAPCO’s evapSelect selection program for unit sound levels. If a detailed analysis or full octave band data sheet is required for your application, please consult your EVAPCO Sales Representative.

NOTE: These low sound options may impact the overall installed dimensions of the ATC-DC Evaporative Condenser selected.

Pulse~Pure® Water Treatment System

The ATC-DC is available with EVAPCO’s optionalPulse~Pure® non-chemical water treatment system. ThePulse~Pure® Water Treatment System utilizes pulsed-power technology to provide CHEMICAL FREE Water Treatment and is an environmentally responsible alternative for treating water in evaporative cooled equipment. It does not release harmful by-products to the environment and eliminates costly chemicals completely from cooler drift and blowdown. The Pulse~Pure® system delivers short, high-frequency bursts of low energy electromagnetic fields to the recirculating water in the ATC-DC and will:

- Control Bacteria to Levels Well Below Most Chemical Water Treatment Programs

- Control the Formation of Mineral Scale on Heat-Exchange Surfaces.

- Save Water by Operating at Higher Cycles of Concentration

- Yield Corrosion Rates Equivalent to Chemical Water Treatment

More benefits of offering EVAPCO’s Pulse~Pure® Water Treatment System on the new ATC-DC are:

    - Pulse~Pure® Factory Mounting - Factory Installation of the Pulse~Pure® System Guarantees
      Your Water Treatment is Installed to Factory Specifications.

    - Integral Cutting Edge Conductivity Control and Blowdown Packages that are contained in a
      single feeder panel:

Conductivity Control Package – Measures Conductivity Utilizing a Non-Fouling Torodial Probe
and Features:

   - One power connection of 120 volt or 460 volt is all that is required.

   - USB port for downloadable 60 day audit trail of system operation.

   - Self draining conductivity loop.

Motorized Blowdown Valve – Standard for the most reliable operation in bleed control. Three-way valve operation provides good bleed flow without a standing column of water.

Because ongoing water treatment service is an absolute requirement for any evaporative cooled system, each purchase of a Pulse~Pure® Water Treatment System includes, as standard, a 1 year water treatment service and monitoring contract provided by your EVAPCO Representative EVAPCO’s Pulse~Pure® system offers ATC-DC owners a single-source of responsibility for equipment, water treatment and service. Patent #: 7,704,364