835965-UIM-C-08144 Johnson Controls Unitary ProductsPIPING CONNECTIONSThe outdoor condensing unit must be connected to the indoor evapora-tor coil using field supplied refrigerant grade copper tubing that is inter-nally clean and dry. Units should be installed only with the tubing sizesfor approved system combinations as specified in tabular data sheet.The charge given is applicable for total tubing lengths up to 15 feet. SeeApplication Data Part Number 247077 for installing tubing of longerlengths and elevation differences.PRECAUTIONS DURING LINE INSTALLATION1. Install the lines with as few bends as possible. Care must be takennot to damage the couplings or kink the tubing. Use clean harddrawn copper tubing where no appreciable amount of bendingaround obstruction is necessary. If soft copper must be used, caremust be taken to avoid sharp bends which may cause a restriction.2. The lines should be installed so that they will not obstruct serviceaccess to the coil, air handling system, or filter.3. Care must also be taken to isolate the refrigerant lines to minimizenoise transmission from the equipment to the structure.4. The vapor line must be insulated with a minimum of 1/2" foam rubberinsulation (Armaflex or equivalent). Liquid lines that will be exposedto direct sunlight and/or high temperatures must also be insulated.5. Tape and suspend the refrigerant lines as shown. DO NOT allowtube metal-to-metal contact. See Figure 2 "Tubing Hanger".6. Use PVC piping as a conduit for all underground installations asshown in Figure 3 "Underground Installation". Buried lines should bekept as short as possible to minimize the build up of liquid refrigerantin the vapor line during long periods of shutdown7. Pack fiberglass insulation and a sealing material such as permagumaround refrigerant lines where they penetrate a wall to reduce vibra-tion and to retain some flexibility.8. See application part number 247077 for additional piping informa-tion.PRECAUTIONS DURING BRAZING OF LINESAll outdoor unit and evaporator coil connections are copper-to-copperand should be brazed with a phosphorous-copper alloy material suchas Silfos-5 or equivalent. DO NOT use soft solder. The outdoor unitshave reusable service valves on both the liquid and vapor connections.The total system refrigerant charge is retained within the outdoor unitduring shipping and installation. The reusable service valves are pro-vided to evacuate and charge per this instruction.Serious service problems can be avoided by taking adequate precau-tions to ensure an internally clean and dry system.PRECAUTIONS DURING BRAZING SERVICE VALVEPrecautions should be taken to prevent heat damage to service valvesby wrapping a wet rag around it as shown in Figure 4 "Heat Protection".Also, protect all painted surfaces, insulation, and plastic base duringbrazing. After brazing, cool joint with wet rag.The valve can be opened by removing the plunger cap and fully insert-ing a hex wrench into the stem and backing out counter-clockwise untilvalve stem just touches the chamfered retaining wall.Connect the refrigerant lines using the following procedure:1. Refer to the Tabular Data Sheet for proper vapor and liquid line siz-ing.2. Remove the cap and Schrader core from both the liquid and vaporservice valve service ports at the outdoor unit. Connect low pressurenitrogen to the liquid line service port.This system uses R-410A refrigerant which operates at higher pres-sures than R-22. No other refrigerant may be used in this system.Gauge sets, hoses, refrigerant containers, and recovery systemsmust be designed to handle R-410A. If you are unsure, consult theequipment manufacturer.Never install a suction-line filter drier in the liquid line of an R-410Asystem. Failure to follow this warning can cause a fire, injury ordeath.Using a larger than specified line size could result in oil return prob-lems. Using too small a line will result in loss of capacity and otherproblems caused by insufficient refrigerant flow. Slope horizontalvapor lines at least 1" every 20 feet toward the outdoor unit to facili-tate proper oil return.FIGURE 2: Tubing HangerNOTICEA0151-001SHEET METAL HANGERLIQUIDLINEINCORRECTCORRECTINSULATED VAPOR LINETAPEFIGURE 3: Underground InstallationDry nitrogen should always be supplied through the tubing while itis being brazed, because the temperature is high enough to causeoxidation of the copper unless an inert atmosphere is provided. Theflow of dry nitrogen should continue until the joint has cooled.Always use a pressure regulator and safety valve to insure that onlylow pressure dry nitrogen is introduced into the tubing. Only a smallflow is necessary to displace air and prevent oxidation.This is not a backseating valve. The service access port has avalve core. Opening or closing valve does not close service accessport.If the valve stem is backed out past the chamfered retaining wall,the O-ring can be damaged causing leakage or system pressurecould force the valve stem out of the valve body possibly causingpersonal injury.Do not leave the system open to the atmosphere. Unit damagecould occur due to moisture being absorbed by the POE oil in thesystem. This type of oil is highly susceptible to moisture absorp-tion.TO INDOOR COIL TO OUT DOOR UNI TLIQUID LINECAPPVCCONDU ITINSULATEDVAPOR LINEA0152-001