INSTALLATION INSTRUCTIONSR- 410A Split System Heat PumpsN4H4 / R4H4 / WCH4These instructions must be read and understood completely before attempting installation.NOTE: Read the entire instruction manual before starting theinstallation.SAFETY CONSIDERATIONSImproper installation, adjustment, alteration, service, maintenance,or use can cause explosion, fire, electrical shock, or otherconditions which may cause death, personal injury, or propertydamage. Consult a qualified installer, service agency, or yourdistributor or branch for information or assistance. The qualifiedinstaller or agency must use factory–authorized kits or accessorieswhen modifying this product. Refer to the individual instructionspackaged with the kits or accessories when installing.Follow all safety codes. Wear safety glasses, protective clothing,and work gloves. Use quenching cloth for brazing operations.Have fire extinguisher available. Read these instructionsthoroughly and follow all warnings or cautions included inliterature and attached to the unit. Consult local building codes andcurrent editions of the National Electrical Code (NEC) NFPA 70.In Canada, refer to current editions of the Canadian electrical codeCSA 22.1.Recognize safety information. This is the safety–alert symbol !! .When you see this symbol on the unit and in instructions ormanuals, be alert to the potential for personal injury.Understand these signal words; DANGER, WARNING, andCAUTION. These words are used with the safety–alert symbol.DANGER identifies the most serious hazards which will result insevere personal injury or death. WARNING signifies hazardswhich could result in personal injury or death. CAUTION is usedto identify unsafe practices which may result in minor personalinjury or product and property damage. NOTE is used to highlightsuggestions which will result in enhanced installation, reliability, oroperation.INSTALLATION RECOMMENDATIONSNOTE: In some cases noise in the living area has been traced togas pulsations from improper installation of equipment.1. Locate unit away from windows, patios, decks, etc. whereunit operation sound may disturb customer.2. Ensure that vapor and liquid tube diameters are appropriatefor unit capacity.3. Run refrigerant tubes as directly as possible by avoiding unnecessary turns and bends.4. Leave some slack between structure and unit to absorb vibration.5. When passing refrigerant tubes through the wall, seal opening with RTV or other pliable silicon–based caulk (see Fig.1).6. Avoid direct tubing contact with water pipes, duct work,floor joists, wall studs, floors, and walls.7. Do not suspend refrigerant tubing from joists and studs witha rigid wire or strap which comes in direct contact withtubing (see Fig. 1).8. Ensure that tubing insulation is pliable and completely surrounds vapor tube.9. When necessary, use hanger straps which are 1 in. wide andconform to shape of tubing insulation (see Fig. 1).10. Isolate hanger straps from insulation by using metal sleevesbent to conform to shape of insulation.OUTDOOR WALLINDOOR WALLCAULKLIQUID TUBEWARNING!ELECTRICAL SHOCK HAZARDFailure to follow this warning could result in personal injuryor death.Before installing, modifying, or servicing system, mainelectrical disconnect switch must be in the OFF position.There may be more than 1 disconnect switch. Lock out andtag switch with a suitable warning label.!WARNINGSUCTION TUBEINSULATIONTHROUGH THE WALLJOISTHANGER STRAP(AROUND SUCTIONTUBE ONLY)INSULATIONSUCTION TUBEEXPLOSION HAZARDFailure to follow this warning couldresult in death, serious personal injury,and/or property damage.Never use air or gases containingoxygen for leak testing or operatingrefrigerant compressors. Pressurizedmixtures of air or gases containingoxygen can lead to an explosion.1” (25.4 mm)MINLIQUID TUBESUSPENSIONA07588Fig. 1 – Connecting Tubing Installation428 01 5107 03 12/15/17

When outdoor unit is connected to factory–approved indoor unit,outdoor unit contains system refrigerant charge for operation withAHRI rated indoor unit when connected by 15 ft. (4.57 m) offield–supplied or factory accessory tubing. For proper unitoperation, check refrigerant charge using charging informationlocated on control box cover and/or in the Check Charge section ofthis instruction.IMPORTANT: Maximum liquid–line size is 3/8–in. OD for allresidential applications including long line.IMPORTANT: Always install the factory–supplied liquid–linefilter drier. Obtain replacement filter driers from your distributor orbranch.INSTALLATIONIMPORTANT: Effective January 1, 2015, all split system andpackaged air conditioners must be installed pursuant to applicableregional efficiency standards issued by the Department of Energy.!CAUTIONCUT HAZARDFailure to follow this caution may result in personal injury.Sheet metal parts may have sharp edges or burrs. Use care andwear appropriate protective clothing and gloves when handlingparts.Check Equipment and Job SiteUnpack UnitMove to final location. Remove carton taking care not to damageunit.Inspect EquipmentElevate unit per local climate and code requirements to provideclearance above estimated snowfall level and ensure adequatedrainage of unit. If using accessory support feet, use installationinstructions from kit for installation.!CAUTIONUNIT DAMAGE HAZARDFailure to follow this caution may result in equipment damage orimproper operation.To prevent damage to the unit, ensure that it is located with thesupports such that the unit is stable in all circumstances includingadverse conditions.Clearance RequirementsWhen installing, allow sufficient space for airflow clearance,wiring, refrigerant piping, and service. Allow 24 in. (609.6 mm)clearance to service end of unit and 48 in. (1219.2 mm) (aboveunit. For proper airflow, a 6–in. (152.4 mm) clearance on 1 side ofunit and 12–in. (304.8 mm) on all remaining sides must bemaintained. Maintain a distance of 24 in. (609.6 mm) betweenunits or 18 in. (457.2 mm) if no overhang within 12 ft. (3.66 m).Position so water, snow, or ice from roof or eaves cannot falldirectly on unit.NOTE: 18” (457.2 mm) clearance option described above isapproved for outdoor units with wire grille coil guard only.Units with louver panels require 24” (609.6 mm) between units.On rooftop applications, locate unit at least 6 in. above roofsurface.3/8–in. (9.53 mm) Dia.Tiedown Knockouts inBasepan(2) PlacesFile claim with shipping company prior to installation if shipmentis damaged or incomplete. Locate unit rating plate on unit cornerpanel. It contains information needed to properly install unit.Check rating plate to be sure unit matches job specifications.Install on a Solid, Level Mounting PadIf conditions or local codes require the unit be attached to pad, tiedown bolts should be used and fastened through knockoutsprovided in unit base pan. Refer to unit mounting pattern in Fig. 2to determine base pan size and knockout hole location.For hurricane tie downs, contact distributor for details and PECertification (Professional Engineer), if required.On rooftop applications, mount on level platform or frame. Placeunit above a load–bearing wall and isolate unit and tubing set fromstructure. Arrange supporting members to adequately support unitand minimize transmission of vibration to building. Consult localcodes governing rooftop applications.Roof mounted units exposed to winds above 5 mph may requirewind baffles. Consult the Service Manual – Residential SplitSystem Air Conditioners and Heat Pumps for wind baffleconstruction.NOTE: Unit must be level to within 2 ( 3/8 in/ft, 9.5 mm/m)per compressor manufacturer specifications.Elevate Unit!CAUTION23 X 23(585 X 585)26 X 26(660 X 660)31–1/2 X 31–1/2(800 X 800)35 X 35(889 X 889)View From TopTIEDOWN KNOCKOUT LOCATIONS in. (mm)ABC7–3/4 (196.8)4–13/32 (111.9)18–1/32 (457.9)9–1/8 (231.8)4–7/16 (112.7)21–1/4 (539.8)9–1/8 (231.8)6–9/16 (166.7)24–11/16 (627.1)9–1/8 (231.8)6–9/16 (166.7)28–7/16 (722.3)Fig. 2 – Tiedown Knockout LocationsA05177Operating AmbientThe minimum outdoor operating ambient in cooling mode withoutaccessory is 55 F (12.78 C), and the maximum outdoor operatingambient in cooling mode is 125 F (51.67 C). The maximumoutdoor operating ambient in heating mode is 66 F (18.89 C).Check Defrost ThermostatUNIT DAMAGE HAZARDFailure to follow this caution may result in equipment damage orimproper operation.Unit must be kept free of an accumulation of water and/or ice inthe basepan.2UNIT BASE PANDimension in. (mm)Check defrost thermostat to ensure it is properly located andsecurely attached. There is a liquid header with a distributor andfeeder tube going into outdoor coil. At the end of the one of thefeeder tubes, there is a 3/8 in. O.D. stub tube approximately 2 in.(50.8 mm) long (see Fig. 3). The defrost thermostat should belocated on stub tube. Note that there is only one stub tube usedwith liquid header, and on most units it is the bottom circuit.Specifications subject to change without notice.428 01 5107 03

FEEDER TUBESTUB TUBEDEFROSTTHERMOSTATA97517Fig. 3 – Defrost Thermostat LocationTable 1 – Accessory UsageStandardREQUIRED FORSEA COAST APPLICATIONS(Within 2 miles / 3.22 km)StandardYesYesNoCrankcase HeaterYesYesNoEvaporator Freeze ThermostatHard Shutoff TXVIsolation RelayLiquid Line Solenoid ValveLow Ambient SwitchSupport FeetYesYesYesNoYesRecommendedNoYesNoSee Long–Line Application atorCompressor Start Assist Capacitor andRelayREQUIRED FOR LOW–AMBIENTCOOLING APPLICATIONS(Below 55 F / 12.8 C)StandardREQUIRED FORLONG LINE APPLICATIONS** For tubing line sets between 80 and 200 ft. (24.38 and 60.96 m) and/or 20 ft. (6.09 m) vertical differential, refer to Residential Piping and Longline Guideline. .Make Piping ConnectionsWARNING!PERSONAL INJURY AND ENVIRONMENTALHAZARDFailure to follow this warning could result in personal injuryor death.Relieve pressure and recover all refrigerant before systemrepair or final unit disposal.Use all service ports and open all flow–control devices,including solenoid valves.!CAUTIONOutdoor Unit Connected To Factory Approved IndoorUnitOutdoor unit contains approximate system refrigerant charge foroperation with approved AHRI rated indoor unit when connectedby 15 ft (4.57 m) of field–supplied or factory–accessory tubing,and factory supplied filter drier. Some indoor units requireadditional subcooling to achieve optimal heating performance.Using Table 5 or 6 – Additional Subcooling Required, checkrefrigerant charge for maximum efficiencyService ValvesUNIT DAMAGE HAZARDFailure to follow this caution may result in equipment damageor improper operation.If ANY refrigerant tubing is buried, provide a 6–in (152.4mm). vertical rise at service valve. Refrigerant tubing lengthsup to 36–in (914.4 mm). may be buried without further specialconsideration. Do not bury lines longer than 36 in (914.4 mm).Outdoor units may be connected to indoor section using accessorytubing package or field–supplied refrigerant grade tubing of correctsize and condition. For tubing requirements beyond 80 ft,substantial capacity and performance losses can occur. Followingthe recommendations in the Residential Piping and Long LineGuideline will reduce these losses. Refer to Table 1 for accessoryrequirements. Refer to Table 2 for field tubing diameters.428 01 5107 03There are no buried–line applications greater than 36 in. (914.4mm)If refrigerant tubes or indoor coil are exposed to atmosphere, theymust be evacuated to 500 microns to eliminate contamination andmoisture in the system.Service valves are closed and plugged from the factory. Outdoorunits are shipped with a refrigerant charge sealed in the unit. Leavethe service valves closed until all other refrigerant system work iscomplete or the charge will be lost. Leave the plugs in place untilline set tubing is ready to be inserted.Heat pumps require a piston metering device in the liquid servicevalve for proper heating operation. Piston is shipped in the pistonbody of the liquid service valve, temporarily held in place with aplastic cap. Do not remove the plastic cap until line set tubing isready to be installed.Refer to Fig. 4 and follow these steps for piston installation:1. Remove plastic cap holding piston in piston body of liquidservice valve.2. Check that piston size (stamped on side of piston) matcheswith number listed on unit rating plate. Return piston topiston body of liquid service valve (either direction).Specifications subject to change without notice.3

3. Find plastic bag taped to unit containing copper adaptertube, brass nut, and plastic washer.4. Install plastic washer in the seat inside piston body.5. Fit brass nut onto adapter tube and install tube onto liquidservice valve. Tighten nut finger tight, then wrenchadditional ½ turn only [15- ft lbs (20.3 N- m)]. Overtightening may damage the plastic washer and servicevalve’s piston body.For Vapor Service Valve - remove valve core from schrader porton Service Valve BEFORE brazing.This helps preventoverheating and damage to valve seals (refer to Fig. 5). Replacevalve core when brazing is completed.WARNING!FIRE HAZARDFailure to following this warning could result in personalinjury, death and/or property damage.BRASS NUTADAPTER TUBEPLASTIC WASHERRefrigerant and oil mixture could ignite and burn as it escapesand contacts brazing torch. Make sure the refrigerant charge isproperly removed from both the high and low sides of thesystem before brazing any component or lines.PISTONPISTON BODYLIQUID SERVICE VALVEA14235Fig. 4 – Liquid Service Valve with Heating Piston andAdapter TubeClean line set tube ends with emery cloth or steel brush. Removeany grit or debris.Insert line set tube ends into service valve tube stubs.Apply heat absorbing paste or heat sink product between servicevalve and joint. Wrap service valves with a heat sinking materialsuch as a wet cloth.Braze joints using a Sil- Fos or Phos- copper alloy.Table 2 – Refrigerant Connections and Recommended Liquidand Vapor Tube Diameters (In.)LIQUIDSERVICE VALVEVALVE CORE*A14236Fig. 5 – Vapor Service ValveConnect vapor tube to fitting on outdoor unit vapor service valves(see Table 2). Connect liquid tubing to adapter tube on liquidservice valve. Use refrigerant grade tubing.CAUTIONUNIT DAMAGE HAZARDFailure to follow this caution may result in equipmentdamage or improper operation.Service valves must be wrapped in a heat–sinking materialsuch as a wet cloth while brazing.Apply heat absorbing paste or heat sink product between servicevalve and joint. Wrap service valves with a heat sinking materialsuch as a wet cloth.After wrapping service valve with a wet cloth, tubing set can bebrazed to service valve using either silver bearing or non–silverbearing brazing material. Do not use soft solder (materials whichmelt below 800 F/427 C). Consult local code requirements.NOTE: Some outdoor units contain a mechanical fitting at theliquid distributor. This connection is not field serviceable andshould not be disturbed.NOTE: For Liquid Service Valve - Braze lineset to adapter tubeBEFORE bolting adapter to valve. This helps prevent overheatingand damage to plastic washer or o- eterTubeDiameter18, 24, 303/83/83/43/436, 42, 483/83/87/87/8603/83/87/81–1/8Units are rated with 25 ft. (7.6 m) of lineset. See Product Data sheet for performancedata when using different size and length linesets.Notes:1. Do not apply capillary tube indoor coils to these units.2. For Tubing Set lengths between 80 and 200 ft. (24.38 and 60.96 m) horizontal or20 ft. (6.09 m) vertical differential 250 ft. (76.2 m) Total Equivalent Length, refer tothe Residential Piping and Longline Guideline – Air Conditioners and Heat Pumpsusing R- 410A refrigerant.Installing with Indoor PistonBrazing Connections!RATED VAPORUNIT SIZEHeat pumps with piston indoor ratings are shipped with the correctpiston size in the accessory bag. Check piston size shipped withindoor unit to see if it matches required indoor piston size. If itdoes not match, replace indoor piston with correct piston sizewhich is listed on the rating plate.NOTE: Heat pumps without piston indoor ratings may beinstalled as a replacement component in a piston system. Wheninstalling a non- piston rated heat pump with a piston indoor thecorrect indoor piston must be installed. When not listed on therating plate the correct piston size is listed in the product data.Replacement pistons can be ordered from ReplacementComponents.13/16” BRASS HEX NUTTEFLON SEALTEFLON RINGS3/4” BRASS HEX BODY“H” DISTRIBUTORPISTONPISTON RETAINERA10342Fig. 6 – Indoor Piston InstallationSpecifications subject to change without notice.428 01 5107 03

Refer to Fig. 7 and install filter drier as follows:1. Braze 5 in. (127 mm) liquid tube to the indoor coil.2. Wrap filter drier with damp cloth.3. Braze filter drier to 5 in. (127 mm) long liquid tube fromstep 1.4. Connect and braze liquid refrigerant tube to the filter drier.IMPORTANT: Installation of the filter drier in liquid line LEAK INSYSTEMMICRONSInstall Liquid Line Filter Drier IndoorVACUUM TIGHTTOO WETTIGHTDRY SYSTEM012345MINUTES67A95424A95424Fig. 8 – Deep Vacuum GraphFinal Tubing CheckA05227Fig. 7 – Liquid Line Filter DrierCAUTION!UNIT DAMAGE HAZARDFailure to follow this caution may result in equipment damageor improper operation.Installation of filter drier in liquid line is required.Evacuate Refrigerant Tubing and Indoor Coil!CAUTIONIMPORTANT: Check to be certain factory tubing on both indoorand outdoor unit has not shifted during shipment. Ensure tubes arenot rubbing against each other or any sheet metal. Pay closeattention to feeder tubes, making sure wire ties on feeder tubes aresecure and tight.Be sure field wiring complies with local and national fire, safety,and electrical codes, and voltage to system is within limits shownon unit rating plate. Contact local power company for correction ofimproper voltage. See unit rating plate for recommended circuitprotection device.NOTE: Operation of unit on improper line voltage constitutesabuse and could affect unit reliability. See unit rating plate. Do notinstall unit in system where voltage may fluctuate above or belowpermissible limits.Make Electrical Connections!UNIT DAMAGE HAZARDFailure to follow this caution may result in equipmentdamage or improper operation.Never use the system compressor as a vacuum pump.Refrigerant tubes and indoor coil should be evacuated using therecommended deep vacuum method of 500 microns. The alternatetriple evacuation method may be used (see triple evacuationprocedure in service manual). Always break a vacuum with drynitrogen.Deep Vacuum MethodThe deep vacuum method requires a vacuum pump capable ofpulling a vacuum of 500 microns and a vacuum gage capable ofaccurately measuring this vacuum depth. The deep vacuum methodis the most positive way of assuring a system is free of air andliquid water. A tight dry system will hold a vacuum of 1000microns after approximately 7 minutes. (See Fig. 8.)WARNINGELECTRICAL SHOCK HAZARDFailure to follow this warning could result in personal injury ordeath.Do not supply power to unit with compressor terminal boxcover removed.NOTE: Use copper wire only between disconnect switch and unit.NOTE: Install branch circuit disconnect of adequate size per NECto handle unit starting current. Locate disconnect within sight fromand readily accessible from unit, per Section 440–14 of NEC.Route Ground and Power WiresRemove access panel to gain access to unit wiring. Extend wiresfrom disconnect through power wiring hole provided and into unitcontrol box.Connect Ground and Power Wires!WARNINGELECTRICAL SHOCK HAZARDFailure to follow this warning could result in personal injury ordeath.The unit cabinet must have an uninterrupted or unbrokenground to minimize personal injury if an electrical fault shouldoccur. The ground may consist of electrical wire or metalconduit when installed in accordance with existing electricalcodes.428 01 5107 03Specifications subject to change without notice.5

Connect ground wire to ground connection in control box forsafety. Connect power wiring to contactor as shown in Fig. 9.DISCONNECTPER N.E.C. AND/ORLOCAL CODESCONTACTORHP THERMOSTAT24 VAC HOTRRR24 VAC COMCCCWIRING3 PHASE ONLYCOOL/HEATSTAGE 1YINDOOR FANGRVS COOLINGOEMERGENCYHEATEEGROUNDLUGA94025Fig. 9 – Line ConnectionsW2*YW3 *BLUEFIELD GROUNDWIRINGW2 *W2HEAT STAGE 2FIELD POWERHEATPUMPTYPICALFAN COILGO* IF AVAILABLELEGEND24-V FACTORY WIRING24-V FIELD WIRINGFIELD SPLICE CONNECTIONODTOUTDOOR THERMOSTATEHREMERGENCY HEAT RELAYSHRSUPPLEMENTAL HEAT RELAYA02325 / A97413Fig. 11 – Generic Wiring Diagrams(See thermostat Installation Instructionsfor specific unit combinations)A00010Fig. 10 – 3–Phase Monitor Control(Applies to 3–Phase Units Only)Table 3 – 3–Phase Monitor LED IndicatorsLEDOFFFLASHINGONSTATUSNo call for compressor operationReversed phaseNormalConnect Control WiringRoute 24v control wires through control wiring grommet andconnect leads to control wiring. See Thermostat InstallationInstructions for wiring specific unit combinations. (See Fig. 11.)Use No. 18 AWG color–coded, insulated (35 C minimum) wire. Ifthermostat is located more than 100 ft (30.5 m) from unit, asmeasured along the control voltage wires, use No. 16 AWGcolor–coded wire to avoid excessive voltage drop.All wiring must be NEC Class 2 and must be separated fromincoming power leads.Use furnace transformer, fan coil transformer, or accessorytransformer for control power, 24v/40va minimum.NOTE: Use of available 24v accessories may exceed theminimum 40va power requirement. Determine total transformerloading and increase the transformer capacity or split the load withan accessory transformer as required.6Final Wiring CheckIMPORTANT: Check factory wiring and field wire connectionsto ensure terminations are secured properly. Check wire routing toensure wires are not in contact with tubing, sheet metal, etc.Compressor Crankcase HeaterWhen equipped with a crankcase heater, furnish power to heater aminimum of 24 hr before starting unit. To furnish power to heateronly, set thermostat to OFF and close electrical disconnect tooutdoor unit.A crankcase heater is required if refrigerant tubing is longer than80 ft (23.4 m), or when outdoor unit is 20 ft (6.09 m) below indoorunit. Refer to the Residential Piping and Long Line Guideline.Install Electrical AccessoriesRefer to the individual instructions packaged with kits oraccessories when installing.Start–Up!CAUTIONPERSONAL INJURY HAZARDFailure to follow this caution may result in personal injury.Wear safety glasses, protective clothing, and gloves whenhandling refrigerant and observe the following:S Front seating service valves are equipped with Schrader valves.Specifications subject to change without notice.428 01 5107 03

!HeatingCAUTIONENVIRONMENTAL HAZARDFailure to follow this caution may result in environmentaldamage.Federal regulations require that you do not vent refrigerant tothe atmosphere. Recover during system repair or final unitdisposal.!CAUTIONUNIT OPERATION AND SAFETY HAZARDFailure to follow this caution may result in personal injury,equipment damage or improper operation.S Do not overcharge system with refrigerant.S Do not operate unit in a vacuum or at negative pressure.S Do not disable low pressure switch in scroll compressorapplications.S Compressor dome temperatures may be hot.Follow these steps to properly start up system:1. After system is evacuated, fully open liquid and vapor service valves.2. Unit is shipped with valve stem(s) front seated (closed) andcaps installed. Replace stem caps after system is opened torefrigerant flow (back seated). Replace caps finger–tight andtighten with wrench an additional 1/12 turn.3. Close electrical disconnects to energize system.4. Set room thermostat at desired temperature. Be sure setpoint is below indoor ambient temperature.5. Set room thermostat to HEAT or COOL and fan control toON or AUTO mode, as desired. Operate unit for 15minutes. Check system refrigerant charge.Sequence of OperationTurn on power to indoor and outdoor units. Transformer isenergized.CoolingOn a call for cooling, thermostat makes circuits R–O and R–Y, andR–G. Circuit R–O energizes reversing valve, switching it tocooling position. Circuit R–Y energizes contactor, starting outdoorfan motor and compressor circuit. R–G energizes indoor unitblower relay, starting indoor blower motor on high speed.When thermostat is satisfied, its contacts open, de–energizingcontactor and blower relay. Compressor and motors should stop.NOTE: If indoor unit is equipped with a time–delay relay circuit,the indoor blower will run an additional 90 seconds to increasesystem efficiency.428 01 5107 03On a call for heating, thermostat makes circuits R–Y and R–G.Circuit R–Y energizes contactor, starting outdoor fan motor andcompressor. Circuit R–G energizes indoor blower relay, startingblower motor on high speed.Should temperature continue to fall, R–W2 is made throughsecond–stage room thermostat. Circuit R–W2 energizes a relay,bringing on first bank of supplemental electric heat and providingelectrical potential to second heater relay (if used). If outdoortemperature falls below setting of outdoor thermostat (fieldinstalled option), contacts close to complete circuit and bring onsecond bank of supplemental electric heat.When thermostat is satisfied, its contacts open, de–energizingcontactor and relay. All heaters and motors should stop.DefrostThe defrost control is a time/temperature control which includes afield selectable (quick–connects located at board edge) time periodbetween defrost cycles (30, 60, or 90 minutes), factory set to either60 or 90 minutes.The electronic defrost timer sequence is enabled when the T1 inputon the board is energized. The timer starts only when the defrostthermostat is closed and the contactor is energized.Defrost mode is identical to cooling mode except that outdoor fanmotor stops and second–stage heat is turned on to continuewarming conditioned spaces.To initiate defrost, the defrost thermostat must be closed. This canbe accomplished as follows:1. Turn off power to outdoor unit.2. Disconnect outdoor fan motor lead from OF2 on controlboard (see Fig. 12). Tape lead to prevent grounding.3. Restart unit in heating mode, allowing frost to accumulateon outdoor coil.4. After a few minutes in heating mode, liquid line temperature should drop below closing point of defrost thermostat(approximately 30 F/–1.11 C).5. Short between speedup terminals with a flat–blade screwdriver. This reduces the timing sequence to 1/25th of original time. (See Table 4.)6. When you hear reversing valve change position, removescrewdriver immediately; otherwise, control will terminatenormal 10–minute defrost cycle in approximately 2seconds.NOTE: Length of defrost cycle is dependent upon length of timeit takes to remove screwdriver from test pins after reversing valvehas shifted.7. Unit will remain in defrost for remainder of defrost cycletime or until defrost thermostat reopens at approximately65 F (18.33 C) coil temperature of liquid line.8. Turn off power to outdoor unit and reconnect fan motorlead to OF2 on control board.Specifications subject to change without notice.7

OUTDOOR FANRELAYDEFROST THERMOSTATMUST BE CLOSED BEFOREDEFROST TIMER BEGINST1 - ENABLES DEFROSTTIMER.MUST BEENERGIZED FORDEFROST TIMERTO STARTY OUTPUT TO PRESSURESWITCHES AND CONTACTORC - COMMONO - REVERSING VALVESPEEDUPTHERMOSTAT INPUTSA05332Fig. 12 – Defrost ControlTable 4 – Defrost Control Speedup–Timing SequencePARAMETER30–minute cycle60–minute cycle90–minute cycle10–minute cycle5 35599115.5SPEEDUP(NOMINAL)7 sec12 sec21 sec2 sec1 secCheck ChargeFactory charge amount and desired subcooling are shown on unitrating plate. Additional subcooling may be required to achieveoptimal heating performance based on the installed indoor unit.(see Table 5 or 6).Charging method is shown on information plate inside unit. ForTXV, use subcooling method. For piston, use superheat method.To properly check or adjust charge, conditions must be favorablefor subcooling or superheat charging. Favorable conditions existwhen the outdoor temperature is between 70 F and 100 F(21.11 C and 37.78 C), and the indoor temperature is between70 F and 80 F (21.11 C and 26.67 C). Follow the procedurebelow:Unit is factory charged for 15ft (4.57 m) of lineset. Adjust chargeby adding or removing 0.6 oz/ft (.018 kg/m) of 3/8 liquid lineabove or below 15ft (4.57 m) respectively.For standard refrigerant line lengths (80 ft/24.38 m or less), allowsystem to operate in cooling mode at least 15 minutes. If conditionsare favorable, check system charge by super heat method for fixedmetering device and subcooling method for TXV. If anyadjustment is necessary, adjust charge slowly and allow system tooperate for 15 minutes to stabilize before declaring a properlycharged system. Refer to Table 5 or 6 for additional subcoolingrequired.If the indoor temperature is above 80 F (26.67 C), and theoutdoor temperature is in the favorable range, adjust system chargeby weight based on line length and allow the indoor temperature todrop to 80 F (26.67 C) before attempting to check system chargeby subcooling method as described above.8If the indoor temperature is below 70 F (21.11 C), or the outdoortemperature is not in the favorable range, adjust charge for line setlength above or below 15ft (4.57 m) only. Charge level should thenbe appropriate for the system to achieve rated capacity. The chargelevel could then be checked at another time when the both indoorand outdoor temperatures are in a more favorable range.NOTE: If line length is beyond 80 ft (24.38 m) or greater than 20ft (6.10 m) vertical separation, See Residential Piping and LongLine Guideline for special charging requirements.Units with Cooling Mode TXVUnits i

literature and attached to the unit. Consult local building codes and current editions of the National Electrical Code (NEC) NFPA 70. In Canada, refer to current editions of the Canadian electrical code CSA 22.1. Recognize safety information. This is the safety–alert symbol!!. When you see this s