Lennox International Inc PWC18E9.2 Mooel no, Powerand Controlwiring, Sequenceof Unit Operation

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IPA.ItTNoIan installation.tt9is made..o96Iin whichDATE12196it is more desirable to mountI SUPERSEDESIthe filter exterior to the,rigunit, in.DO9the returnI.ductPAGE,Owork, or tO .

olherwise, either the permanent filter supplied or a disposable filter may be used. If a disposable filter is used, the minimum area required is as follows:

MOOEL NO.

FILTER AREA(MtN.)

PWC 182

480 sq. in.

PWC 242

480 sq. in.

PWC 302

480 sq. in.

THERMOSTAT

The room thermostatshouldbe locatedon an insidewall where it wilt not be subjectto drafts, sun exposureor heat from electricalfixturesor appliances. Followthemanufacturer'sinstructionsenclosedwith the thermostatfor general installationprocedures.Colorcodedinsulatedwires (#18 AWG)shouldbe used to connectthe thermostattothe unit.

POWERAND CONTROLWIRING

ELECTRICALCONNECTIONS

ALLWIRINGSHOULDBEDONEIN ACCORDANCEWITH NATIONALELECTRICALCODE,ANSI/NFPA NO.70 (LATEST EDITION). IN CANADA(_SAC22.2 Part 1 (LATEST EDITION),OR WITH LOCAL CODES,WHERETHEY PREVAIL.

NOTE: UNITS AREFACTORYWIRED FORA 230 VOLTPOWERSUPPLY. IF POWERSUPPLYIS 208 VOLTS. IT WILL BENECESSARYTO CHANGEA WIRE CONNECTIONON UNIT TRANSFORMERFROM240V TERMINALTO20SV TER- MINAL AS SHOWNON WIRING DIAGRAM.

Usewiring with a temperaturelimitationof 75°C rain. Runthe 208 or 230 volt, 60 hertz electricpowersupplythrough

afuseddisconnectswitch to the controlboxof the unitand connectas shownin the wiringdiagramlocatedon the in- side of the controlaccess panel.

The unit must be electricallygroundedin accordancewith local codesor in the absenceof local codeswith the Na- tional ElectricCodeANSI/NFPA No. 70 (latest edition)or CSA C22.2 Part 1 (latest edition).

Power supplyto the unit must be N.E.C. Class 1, and must complywith all applicablecodes. A fused disconnect switchshouldbe field provided for the unit. The switch must be separatefrom all other circuits. If any of the wire suppliedwith the unit must be replaced, replacementwire must be of the type shownon the wiring diagram.

Electricalwiringmust be sized to minimumcircuitampacitymarkedon the unit. USECOPPERCONDUCTORSONLYI

Eachunit must be wired with a separate branchcircuit and be properlyfused.

SEQUENCEOF UNIT OPERATION

COOLING- Whenthe thermostatis In the coo[ingmode,the O circuitis poweredwhichenergizesthe reversing valve.

Uponcoolingdemand,the thermostatclosescircuitR to Y and G. ClosingR toY closesthe unitcontactor,starting the compressorand outdoorfan. The thermostatautomaticallyclosesRto G circuitwhichalsobringson the indoorblower at thesametime. Uponsatisfyingcoolingdemand,the thermostatwill openthe abovecircuitsand openthe main con- tactor, stoppingthe compressorand outdoorfan. If the unitis equippedwith a time delay,the blowerwill continueto operate.for 90 secondswhich improvessystem efficiency.

HEATING- Uponheating demandthe thermostatclosescircuit R to Y closingthe unitcontactor,starting the com- pressorand outdoorfan. The reversing valveis notenergizedin the heating mode.Thethermostatagainautomatical- ly bringson the indoorblower at the same time. The secondstageof the thermostatclosescircuit Rto W closingthe unitsequencers,bringthe auxiliaryelectricheaton. Uponsatisfyingheatingdemandthethermostatopensabovecir- cuits and stopsunit operation.

DEFROSTCYCLE- If outdoor ambient conditionsare such that frost forms on the outdoorcoil, the defrost control monitors the need for and initiates and terminatesdefrost cyclesas neccessary to maintain system performance.The

defrost controlis time/temperature initiated and temperature terminated with a maximum defrost time (time-out)of

10 minutes. Time betweendefrost cyclesis pre-setat 60 minuteintervalsat the factory, but can be field adjustedto

30, 60, or 90 minutes. See illustrationfor field adjustmentof defrosttiming. For best performancein RegionIV, the PWC242 defrostinterval should be adjusted to 30 minutes.

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Contents IIIIIIIIIIIIll Euctricalwiring PWCInstallationCAUT,ON PWC Drain InstallationTable t Application LimitationsAirFilter Minimum Required Surface Area for Disposable FiltersHeating Defrost ControlDefrost Cycle Suction Conducting any maintenance proceduresCAPACrR-RUN Connection Diagram PWC with 5, 7 or 10 KW Heat StripPWC with 15 KW Heat Strip Connection DiagramFin-r== Connection Diagram PWC with No Heat StripWarranty on Replacement Components Warranty BeginsInstalled by Lennox International Company AgeFrontof Instailing Wall Sleeve from Inside Z9- -,4LENNOXInternationalInc. Company Armstrong AIR Conditioning INCElectric Heating PWC 242 A-1AGeneral Inspectionof ShipmentCondensatedrain With Wall SleeveInstructionforsupportingpwcunits PA.T.OI. ,,,,,,.0 I, 0,I I Suerseoesi 00I PAE,O,OAIR Filter LimitationsCool Heat DuctworkMooel no Powerand ControlwiringSequenceof Unit Operation Idnstallation Electricheating Location NEW PART.OI DArEI 4-5-9I SupersedesPA,TNOI 4tt94OOB4I DA EI 41594SUPERSEDESI Newi page OFtO Modelno Filterareamin PartnoPWC Suctionsuperheat Defrostcontrolsettingdefrosttest CycletimeT2 = 60 Minutes System PerformancePhysicaland Electricaldata Normal Maintenance9Do9IOA.El .-5-lgSUE.SEOESl .EW I ,GEgOF,O Bujeiiiiii Iiiiii Installation Keep this Manual in a Safe Place for Ready Reference ForwardPartNo SOF089 Supersedes 30790G082 Operation Instructions Table of Contents InstallationMaintenance and Service 30?90F089 Date 149 Supersedes307g0F089 Date Supersedes 30790G082Pageof12 Freezing Pan No 307g0F089 Multiple Entry Supply DateSingle Entry Supply PWGI8E7.2Thermostat 30790F089 Date Supersedes 30790G082 Operation Instructions 30790F089 Date 1o89 Supersedes 30790G082

PWC18E14.7, PWC18E4.8, PWC182, PWC24E7.2, PVVC24ElO.7 specifications

Lennox International Inc. is a leading provider of innovative heating, ventilation, and air conditioning (HVAC) solutions. Among its diverse range of products, the company offers various models of packaged water chillers designed for efficiency, performance, and reliability in commercial applications. The PWC18E10.7, PWC302, PWGI8E7.2, PWC182, and PWC242 are notable examples of Lennox's commitment to quality and advanced technology in packaged water chillers.

The Lennox PWC18E10.7 is a high-efficiency chiller featuring a compact design, making it suitable for space-constrained environments. With a cooling capacity of 18 tons, this model utilizes a scroll compressor for reliable operation and low energy consumption. Its advanced microchannel coil technology enhances heat transfer efficiency, allowing for better cooling performance with a reduced refrigerant charge.

The PWC302 is another robust offering, boasting a cooling capacity of 30 tons. This model is designed for outdoor installation, equipped with fully controllable variable-speed fans that adapt to varying load conditions. The PWC302 is notable for its low noise levels, making it ideal for applications where sound restrictions are paramount. Its advanced controls also provide flexibility in managing energy usage, further enhancing its appeal for eco-conscious businesses.

The PWGI8E7.2 is distinguished by its inverter-driven compressor, which allows for precise temperature control and enhanced efficiency. This model, with an 8-ton cooling capacity, is particularly suited for environments requiring consistent cooling. Its compact footprint coupled with high energy efficiency ratings means it can be easily integrated into existing systems while ensuring optimal performance.

The PWC182, another capable unit, is designed with a focus on durability and ease of maintenance. Features such as a corrosion-resistant cabinet and user-friendly access panels make it a practical choice for facilities managers. The PWC182 operates quietly and efficiently, ensuring minimal disruption in operational settings.

Lastly, the PWC242 provides a larger cooling capacity of 24 tons, making it ideal for medium to large commercial spaces. Its advanced refrigerant management system optimizes performance while meeting environmental regulations. All these models incorporate advanced electronic controls, which enhance operational efficiency and provide real-time monitoring capabilities, allowing users to optimize energy consumption based on actual demand.

In summary, Lennox International offers a range of advanced packaged water chillers, including models like the PWC18E10.7, PWC302, PWGI8E7.2, PWC182, and PWC242. Each model features cutting-edge technologies aimed at delivering high efficiency, reliability, and ease of use, making them suitable choices for commercial applications seeking sustainable and effective HVAC solutions.
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