Tjernlund CPC-3 controller enables 'on-demand' …

1 A laundromat contractorand an equipment distribu-tor teamed up to design aunique mechanical systemfor a new facility. The sys-tem provides up to 20,000 CFM of make-up air for 54large commercial dryersfrom two four-square-footroof openings. The brainsof the system is aTjernlund CPC-3 ConstantPressure controller . It senses room pressure andautomatically adjusts tworoof-mounted modulatingfans to deliver the amountof air needed by the dryerswhen they are operating. Multiple benefits for the ownerinclude reduced construction costs, fewer roof penetrations,increased interior comfort for customers and expected energy savings.

2 The system has been operating successfullysince May 2005. A builder of Laundromats for the past 15 years, JonTumpack, owner of TCS Contracting in Romeoville,Illinois, has struggled with issues related to make upair supply. Tumpackteamed up with CliffCurtis, a BusinessDevelopment Specialistfor laundry equipmentdistributor Mac-Gray,to design a better system for the Fox LakeLaundromat. Theywanted an automatedsystem that wouldovercome numerousinstallation and opera-tional issues associatedwith traditional make-up air systems. Traditional systemsare sized to handle theCFM requirements whenall dryers are running at the sametime.

3 Air is typicallydelivered to dryers eitherthrough large exteriorwall or roof louvers orby running ducts fromeach dryer through penetrations in the large openingsprovide enough outsideair when all dryers areoperational, but createproblems when dryersare operating at mini-mum levels. Cold climatelocations are subject to excess cold can also be a concern as typical make-upair openings are large enough for an adult to fitthrough. Often, there is not enough square footageavailable on a roof or outside wall to accommodate the required area for entry of make-up on other sideFox Lake Laundromat is located in Fox Lake, Illinois, features 54 largecommercial dryers that require up to 20,000 CFM of make up for owners include minimal exterior openings, lower constructioncosts and improved dryer performance with lower operating costTjernlund CPC-3 controller enables 'on-demand'make-up air system for 54- dryer laundromatAbove.

4 Tjernlund s CPC-3 ConstantPressure controller senses room pressureand adjusts modulating roof mountedblowers to deliver volume of make up airrequired by dryers in make-up air openings are typically tooclose to the dryer exhausts creating a problem as lintcirculates back into the laundry through the make-upopening. Trying to distance multiple large openingsfrom exhaust can add cost quickly. Tumpack and Curtis quest for a better system started with an Internet search for the latest ventingtechnology that led them to Tjernlund 's CPC-3 ConstantPressure controller .

5 We were looking for a way to create an ondemand" that's why this controller interested us, said Curtis. The CPC-3 controller senses pressure in the interiorspace behind the dryers and ramps the modulatingintake fans up or down to meet the demands of thosedryers in use. The CPC-3 controller is microprocessor-based and compatible with virtually all VFD controlled modulatingfans. The controller is simple to program and operateand offers many options including interfaces with amotorized louver or CO detector. It also has a built inalarm relay that can be interfaced with a building management system.

6 As a provider of the dryers, it is my responsibility tobe sure make up air systems are properly sized, Curtissaid. Over the years, we ve found many installationsthat are because some architects,installers and owners are reluctant to specify large openings in structures where they are needed oradequate space is not available. Tumpack said with a conventional system in the FoxLake Laundromat between 40 and 50 square feet ofroof openings would be required to provide enoughmake-up air for the dryers. With the new system, thereare only two four-square-foot openings.

7 The other element we deal with in this part of thecountry is cold weather, said Tumpack. A passiveT J ERNLUND PRODUCTS, Ninth Street White Bear Lake, MN 55110-6794 Phone: Fax: our web site: Auto-Draft is a registered trademark of Tjernlund Products, Inc. Copyright Tjernlund Products, Inc. All rights reserved CHFL -8500745 make up air system is always at 100 percent opening, no matter if one or all dryers are in use, which means atremendous amount of cold air entering the building onslow laundry days and uncomfortable customers.

8 Curtis noted that with the new system "You can gobehind the dryers on a slow day and not feel any air coming down from the vents. However, on a busy day,when all of the dryers are going at once, there's quite a bit of air blowing down, but you hardly feel air movement at the service entrance behind the dryers. Tumpack noted that the system is not creating a negative or positive pressure it s balanced whether the fans are cranking out 10,000 CFM or 1,000 and Tumpack s new system fits right in with the energy savings theme they are featuring in a newfacilities development program.

9 Since we re using laundry equipment, water heatingand lighting systems that work together, it affords us the opportunity to create more high energy efficientinstallations, Curtis said. Our industry is so dependenton utilities such as right now there is a lot ofbuzz about gas consumption. Two modulating fans provide make up air for all dryersthrough two four-square-foot openings in roof. Large lit display and easy to use soft touch keypad. Primary functions can be programmed via dedicated keys, eliminating scrolling through multiple screens. Additional LED's indicate limit(s) status, VFD operation and fault status.

10 Correct Inducer/Blower rotation is determined by display prompts and changed through DIP switcheson the circuit board. System fault diagnosis readout and retrieval. Built-in alarm alerts building maintenance personnel if system faults. Alarm relay also allows interface with building management CPC-3 Features.