Lennox International Inc. XC21 manual

Page 1 7/2012 506923−01 *2P72012* *P506923-01* E 2012 Lennox Industries Inc. Dallas, T exas, USA THIS MANUAL MUST BE LEFT WITH THE HOMEOWNER FOR FUTURE REFERENCE W ARNING The S tate of California has determined that this product may contain or produce a chemical or chemicals, in very low doses, which may cause serious illness or death. It may als[...]

Page 2 UNIT DIMENSIONS − INCHES (MM) 39−1/2 (1003) 35−1/2 (902) 47 (1 194) 18−1/2 (470) 8 (203) 1 (25) 4−1/2 (1 14) LIQUID LINE INLET ELECTRICAL INLETS SIDE VIEW ACCESS VIEW DISCHARGE AIR 4−5/8 (1 17) BASE WITH ELONGA TED LEGS 16−7/8 (429) 8−3/4 (222) 26−7/8 (683) 3−3/4 (95) 30−3/4 (781) 3−1/8 (79) SUCTIOn LINE INLET UNIT SU[...]

Page 3 XC21 SERIES INST ALL UNIT AW A Y FROM WINDOWS TWO 90 _ ELBOWS INST ALLED IN LINE SET WILL REDUCE LINE SET VIBRA TION PLACEMENT FIGURE 2 Install unit level or , if on a slope, maintain slope tolerance of 2 degrees (or 2 inches per 5 feet [50 mm per 1.5 m]) away from building structure. GROUND LEVEL MOUNTING SLAB BUILDING STRUCTURE DISCHARGE A[...]

Page 4 IMPORT ANT ! If this unit is being matched with an approved line set or indoor unit coil that was previously charged with mineral oil, or if it is being matched with a coil which was manufactured before January of 1999, th e coil and line set must be flushed prior to inst alla- tion. T ake care to empty all existing trap s. Polyol es- ter (P[...]

Page 5 XC21 SERIES STEP 2 −− REFRIGERANT PIPING −− Removing Existing Indoor Metering Device SENSING LINE TEFLON ® RING FIXED ORIFICE BRASS NUT LIQUID LINE ASSEMBL Y (INCLUDES STRAINER) LIQUID LINE ORIFICE HOUSING DISTRIBUT OR TUBES DISTRIBUT OR ASSEMBL Y REMOVE AND DISCARD WHITE TEFLON ® SEAL (IF PRESENT) 1. On fully cased coils, remove t[...]

Page 6 STEP 2 −− REFRIGERANT PIPING −− Brazing Procedures A TTACH THE MANIFOLD GAUGE SET FOR BRAZING LIQUID AND SUCTION / V APOR LINE SERVICE V AL VES OUTDOOR UNIT LIQUID LINE SUCTION / V APOR LINE LIQUID LINE SERVICE VA LV E SUCTION / V APOR LINE SER VICE VA LV E A TT ACH GAUGES INDOOR UNIT SUCTION / V APOR SERVICE PORT MUST BE OPEN AND SE[...]

Page 7 XC21 SERIES CAUTION Brazing alloys and flux cont ain materials which are hazardous to your health. Avoid breathing vapors or fumes from brazing operations. Perform operations only in well−ventilated areas. Wear gloves and protective goggles or face shield to protect against burns. W as h hands with soap and water af ter handling brazing al[...]

Page 8 STEP 3 −− INST ALLING INDOOR EXP ANSION V AL VE This outdoor unit is designed for use in systems that include an exp ansion valve metering device. Se e the XC21 Product Specifications bulletin (EHB) for ap p r o v e d ex p a n s i o n va l v e kit ma t c h − u ps an d ap p l i c a t i o n in f o r m a t i o n . The expansion valve can [...]

Page 9 XC21 SERIES STEP 4 −− LEAK TEST AND EV ACUA TION TO V APOR SER VICE V AL VE HFC−410A MANIFOLD GAUGE SET OUTDOOR UNIT HIGH LOW CONNECT GAUGE SET A. Connect the high pressure hose of an HFC−410A manifold gauge set to the vapor valve service port. NOTE  Normally , the high pressure hose is connected to the liquid line port. However ,[...]

Page 10 STEP 4 −− LEAK TEST AND EV ACUA TION (Continued) A. Open both manifold valves and start the vacuum pum p. B. Evacuate the line set and indoor unit to an absolute pressure of 23,000 microns (29.01 inches of mercury). NOTE  During the early stages of evacuation, it is desirable to close the manifold gauge valve at least once. A rapid r[...]

Page 1 1 XC21 SERIES STEP 5 −− ELECTRICAL −− Circuit Sizing and Wire Routing In the U.S .A., wiring must conf orm wit h current local codes and the cur rent National Elec tric Code (NE C). In Canada, wiring m ust confor m with current local codes and t he current Canadian Elec trical Code (CEC) . Refer to the furnace or a ir handler install[...]

Page 12 NOTE  For proper voltages, select control wires gauge per table below . WIRE RUN LENGTH A WG# INSULA TION TYPE LESS THAN 100’ (30 METERS) 18 TEMPERA TURE RA TING MORE THAN 100’ (30 METERS) 16 35ºC MINIMUM. NOTE  Wire tie provides low voltage wire strain relief and maintains separation of field−installed low and high voltage cir[...]

Page 13 XC21 SERIES STEP 5 −− ELECTRICAL (Continued) −− Out door Control (A175) Jumpers and T erminals 55 50 DEGREE TARGET 45 DEGREE TARGET 40 DEGREE TARGET (DEFAULT) 55 50 45 40 55 50 45 40 55 50 45 40 55 50 45 40 DEGREE TARGET 100 90 DEGREE TARGET 70 DEGREE TARGET 50 DEGREE TARGET 100 90 70 50 DEGREE TARGET 100 90 70 50 100 90 70 50 100 9[...]

Page 14 STEP 5 −− ELECTRICAL (Continued) −− Field Control Wiring Th e following two illustrations provide examples of control wiring connections when using a non−communicating thermostat. For examples of control wiring in complete or p artial communicating systems, see the icomfort t −enabled thermosta t Quick Start Guide which is provi[...]

Page 15 XC21 SERIES Y1 O R W1 G D R Y1 L C C B Y2 Y2 W O DS L T T W2 H H O C L Y2 DS DH G R Y1 W2 W1 1 2 4 5 Furnace ComfortSense [ 7000 Thermostats Catalog # Y0349 or Y2081 XC21 T wo − Stage Air Conditioner Control On − board link Low voltage thermostat wiring 3 1. Thermostat T terminals are used for outdoor sensor input. Use for thermostat’[...]

Page 16 Charging The XC21 unit is factory−charged with enough HFC−410A refrigerant to accommodate a 15−foot length of refrigerant piping. Charge should be checked and adjusted using the tables provided on the charging procedure sticker on the unit access panel. Det ailed information is given in the XC21 Inst allation and Service Procedures ma[...]

Page 17 XC21 SERIES XC21 Field Operational Checklist Unit Readings Cooling*** Heating*** Y1 First S tage Expected results during Y2 demand (toggle switch ON) Y2 Second S tage Y1 First St age Expected results during Y2 demand (toggle switch ON) Y2 Second S tage Compressor V oltage Same Same Amperage Higher Higher Condenser Fan motor Amperage Same or[...]

Page 18 XC21 S tart−Up and Performance Checklist Customer Address Indoor Unit Model Serial Outdoor Unit Model Serial Solar Module Mfg and Model Serial Notes: ST ART−UP CHECKS Refrigerant T ype: Rated Load Amps Actual Amps Rated V olts Actual V olts Condenser Fan Full Load Amps Actual Amps: COOLING MODE V apor Pressure: Liquid Pressure: Supply A[...]

Page 19 XC21 SERIES Homeowner Information CAUTION Before attempting to perform any service or mainte- nance, turn the electrical power to unit OFF at discon- nect switch. Cleaning of th e out door unit’s coil should be performed by a licensed professional service technician (or equivalent). Contact your dealer and set up a schedule (preferably tw[...]