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MULTI MULTI WITH OUTDOOR UNIT ENGINEERING MANUAL Dual-, Tri-, and Five, Six, and Eight-Zone Quad-Zone Multi F Multi F MAX Multi-Zone Heat Pump Outdoor Units 1.5 to 4 Tons...
..........................................17-19 ..........................................20 ................................21 ............................................. 22 ....................................23 ..........................................24 ......................................25-27 ..........................................28-29 Multi F MAX with LGRED Outdoor Unit Product Data ............................30-42 ......................................31 ..........................................32-33 ..........................................35 ................................36 ............................................. 37 ....................................38 ..........................................39 ......................................
UNIT NOMENCLATURE MULTI WITH MULTI Multi-Zone Systems — Outdoor Units 1. Refrigerant K = R32 2. Component U = Outdoor Unit 3. Product Category M = Multi 4. Product Type X = Null 5. Product Grade A = LGRED° 6. Nominal Capacity (Btu/h) 18 = 18,000 Btu/h 30 = 30,000 Btu/h 42 = 42,000 Btu/h...
Features All LG product design criteria have been loaded into the program, making LATS simple to use: double click or drag and drop the component choices. Build systems in Tree Mode where the refrigerant system can be viewed. Switch to a Schematic diagram to see the electrical and communications wiring.
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LATS can generate an Excel GERP report that can be imported into the LG SOPS pricing and ordering system.
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(if applicable) for each indoor unit. Avoid oversizing indoor units in an attempt to increase the air exchange rate in the space. Multi F and Multi F MAX systems are designed for minimum airflow over the coil to maximize latent capacity while cooling, maintain a comfortable, consistent discharge air temperature while heating, and minimize fan motor power consumption.
MANUAL EQUIPMENT MULTI WITH MULTI SELECTION PROCEDURE Choosing the Appropriate Indoor Units, Continued. Examples Example 1 Branch Distribution Unit (PMBD3620ZR) Example 2 Branch Distribution Unit (PMBD3620ZR) First Indoor Unit: Second Indoor Unit: Outdoor Unit: KUMXA421A First Indoor Unit: Second Indoor Unit: Third Indoor Unit: KNMLB181A KNMLB181A...
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In some designs, oversized indoor units may be unavoidable in the case where the smallest size indoor unit available from LG is larger than what is necessary to satisfy the zone load. This scenario may also occur when an indoor unit selection one size down from the selected unit is slightly short of fulfilling the design load requirements, and the designer must choose the next largest size unit.
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MANUAL EQUIPMENT MULTI WITH MULTI SELECTION PROCEDURE Using the Indoor Unit Cooling and Heating Capacity Tables The datapoints shown in the indoor unit cooling and heating capacity charts are based on (and convey) an indoor unit operating with maxi- mum possible refrigerant flow from the outdoor unit and before any derates are applied. In other words, the capacities displayed reflect what the indoor unit would produce if it was the only indoor unit that required capacity, and the outdoor unit did not have to allocate any capacity to another indoor unit.
Table 3: Multi F with LGRED Outdoor Unit (Multiple Piping) to Indoor Unit Refrigerant Line Length Derate. Piping Length (ft.) 16.4...
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MANUAL EQUIPMENT MULTI WITH MULTI SELECTION PROCEDURE Refrigerant Line Length Derates, Continued. Figure 2: Multi F MAX with LGRED Outdoor Unit to Branch Distribution Unit Refrigerant Line Length Derate Chart. 100.0 95.0 Heating capacity 90.0 Cooling 85.0 capacity 80.0 75.0 70.0...
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• If further system design assistance is needed, or you have a latent load is greater than 30%). unique application you would like to discuss, contact your LG sales rep. • Verify that the sensible load of the zone is satisfied.
MULTI F WITH LGRED° OUTDOOR UNIT PRODUCT DATA Mechanical Specifications on page 16 General Data on page 17 Electrical Data on page 20 Functions, Controls, Options, and Accessories on page 21 Dimensions on page 22 Wiring Diagram on page 24...
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General KUMXA301A Outdoor Units. ing units are equipped with one A Multi F with LGRED multi-zone system is comprised of one heat hermetically sealed, digitally pump outdoor unit connected to two, three, or four indoor units us- controlled, inverter driven twin-...
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(WB) and outdoor ambient conditions of 95ºF dry bulb (DB) and 75ºF wet bulb (WB). tables in the "Multi F / Multi F MAX Combination Data Manual" on www.lghvac.com. For performance Rated heating capacity obtained with air entering the indoor unit at 70ºF dry bulb (DB) and 60ºF wet data, see "Multi F / Multi F MAX Performance Data Manual"...
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MULTI F WITH LGRED° OUTDOOR UNIT MULTI WITH MULTI Table 8: Model Number KUMXA181A KUMXA241A KUMXA301A Liquid Line Connection (in., OD) x Qty. 1/4 Flare x 2 1/4 Flare x 3 1/4 Flare x 4 Vapor Line Connection (in., OD) x Qty.
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MULTI F WITH LGRED° OUTDOOR UNIT MULTI WITH MULTI Table 9: ENERGY Low Heating ENERGY Rated Cooling EER2 Rated Heating STAR System Combined With SEER2 HSPF2 Capacity STAR Capacity (Btu/h) (95°F) Capacity (Btu/h) (47°F) (17°F) Cold (Btu/h) Climate Non-Ducted 18,000 13.5...
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MULTI F WITH LGRED° OUTDOOR UNIT MULTI WITH MULTI Table 12: Electrical Data. Indoor Fan Voltage Outdoor Fan Motor Nominal Unit Model Compressor Compressor Motor Hertz Voltage Range MCA MOP LRA Tons Quantity Motor RLA (Min. to Max.) KUMXA181A 22.7 17.0...
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MULTI F WITH LGRED° OUTDOOR UNIT MULTI WITH MULTI Table 13: Functions, Controls, Options, and Accessories. Functions KUMXA181A KUMXA241A KUMXA301A Defrost / Deicing High Pressure Switch Restart Delay (Three [3] Minutes) Self Diagnosis Soft Start Test Function Night Silent Operation...
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MULTI F WITH LGRED° OUTDOOR UNIT MULTI WITH MULTI Figure 4: KUMXA181A, KUMXA241A, KUMXA301A Dimensions. Model: KUMXA181A, KUMXA241A, and KUMXA301A Vapor Piping Service Valve Liquid- Piping Service Valve ODU-IDU Connection Power Wiring Access Hole ODU-IDU Connection Communication Wiring Access Hole 1.
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MULTI F WITH LGRED° OUTDOOR UNIT MULTI WITH MULTI Figure 5: KUMXA181A, KUMXA241A, and KUMXA301A Center of Gravity and Corner Weight Diagram (Appearance may differ than what is depicted below). Table 14: KUMXA181A, KUMXA241A, KUMXA301A Center of Gravity and Corner Weights.
MULTI F WITH LGRED° OUTDOOR UNIT MULTI WITH MULTI Figure 6: KUMXA181A, KUMXA241A, and KUMXA301A Wiring Diagram. Wiring Diagram USE COPPER SUPPLY WIRES. Mot or CN_INPUT Compressor _BROWN CN_MAIN (WH) CN_INPUT _BLUE INVERTER CN_EARTH1 CN_RE ACTOR CN_RE ACTOR CN_PRESS_SW_WH _OUT(RD)
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MULTI F WITH LGRED° OUTDOOR UNIT MULTI WITH MULTI Figure 7: KUMXA181A Refrigerant Flow Diagram. Outdoor Unit Unit: Inch (mm) Condenser Out Ø1/4 (6.35) Inlet Air Temperature Temperature Flare Connection Thermistor Thermistor Electronic Condensing Expansion Temperature Valve Thermistor Main SVC V/V...
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MULTI F WITH LGRED° OUTDOOR UNIT MULTI WITH MULTI Figure 8: KUMXA241A Refrigerant Flow Diagram. Outdoor Unit Unit: Inch (mm) Condenser Out Ø1/4 (6.35) Inlet Air Temperature Temperature Flare Connection Thermistor Thermistor Electronic Condensing Expansion Temperature Valve Thermistor ROOM A...
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MULTI F WITH LGRED° OUTDOOR UNIT MULTI WITH MULTI Figure 9: KUMXA301A Refrigerant Flow Diagram. Outdoor Unit Unit: Inch (mm) Condenser Out Inlet Air Ø1/4 (6.35) Temperature Temperature Flare Connection Thermistor Thermistor Electronic Condensing Expansion Temperature Valve Thermistor ROOM A...
MULTI F WITH LGRED° OUTDOOR UNIT MULTI WITH MULTI Sound Pressure Levels • Figure 10: Acoustic Measurement Location. • Measurements taken with no attenuation and units operating at full load normal operating condition. Microphone • Sound level will vary depending on a range of factors such as construction (acoustic absorption coefficient) of particular area in 3.3 feet...
MULTI F WITH LGRED° OUTDOOR UNIT MULTI WITH MULTI Sound Power Levels Table 19: Sound Power Levels (dB[A]). Sound Power Levels (dB[A]) • Data is valid under diffuse field conditions. Model No. Cooling Heating • Data is valid under nominal operating conditions.
MULTI F MAX WITH LGRED° OUTDOOR UNIT PRODUCT DATA Mechanical Specifications on page 31 General Data on page 32 Electrical Data on page 35 Functions, Controls, Options, and Accessories on page 36 Dimensions on page 37 Wiring Diagram on page 39...
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700 rpm in cooling, and up to pre-coated metal that has been tested in accordance with ASTM 750 rpm in heating. Multi F MAX with LGRED outdoor units have a B-117 salt spray procedure for a minimum of 1,000 hours. Case has horizontal discharge airflow.
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Y-branch accessory (ARBLN03321). At least two indoor units must be connected. For allocated capacity information, see the combination tables in the “Multi F / Multi F MAX with LGRED Combination Data Manual” on www.lghvac.com. For performance data, see “Multi F / Multi F MAX with LGRED Performance Data Manual”...
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MULTI F MAX WITH LGRED° MULTI WITH MULTI OUTDOOR UNIT Table 21: Model Number KUMXA361A KUMXA421A KUMXA481A Liquid Line Connection (in., OD) x Qty. Ø3/8 Flare x 1 Ø3/8 Flare x 1 Ø3/8 Flare x 1 Vapor Line Connection (in., OD) x Qty.
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MULTI F MAX WITH LGRED° MULTI WITH MULTI OUTDOOR UNIT Table 22: ENERGY ENERGY Rated Cooling EER2 Rated Heating Low Heating STAR System Combined With SEER2 HSPF2 STAR Capacity (Btu/h) (95°F) Capacity (Btu/h) (47°F) Capacity (Btu/h) (17°F) Cold Climate Non-Ducted 36,000 14.5...
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MULTI F MAX WITH LGRED° MULTI WITH MULTI OUTDOOR UNIT Table 25: Electrical Data. Indoor Fan Voltage Outdoor Fan Motor Nominal Unit Model Compressor Compressor Motor Hertz Voltage Range MCA MOP LRA Tons Quantity Motor RLA (Min. to Max.) KUMXA361A 32.1...
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MULTI F MAX WITH LGRED° MULTI WITH MULTI OUTDOOR UNIT Table 26: Functions, Controls, Options, and Accessories. Functions KUMXA361A KUMXA421A KUMXA481A Defrost / Deicing High Pressure Switch Restart Delay (Three [3] Minutes) Self Diagnosis Soft Start Test Function Night Silent Operation...
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MULTI F MAX WITH LGRED° MULTI WITH MULTI OUTDOOR UNIT Figure 14: KUMXA361A, KUMXA421A, and KUMXA481A Dimensions. Chassis code : U60A-B Handle Handle Power Wiring / Communication Cable Access Vapor Pipe Holes Connection (Flare) Liquid Pipe Connection (Flare) Air Outlet Notes: 1.
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MULTI F MAX WITH LGRED° MULTI WITH MULTI OUTDOOR UNIT Figure 15: KUMXA361A, KUMXA421A, and KUMXA481A Center of Gravity and Corner Weight Diagram (Appearance may differ than what is depicted below). Table 27: KUMXA361A, KUMXA421A, and KUMXA481A Center of Gravity and Corner Weight Dimensions.
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MULTI F MAX WITH LGRED° MULTI WITH MULTI OUTDOOR UNIT Figure 16: KUMXA361A, KUMXA421A, and KUMXA481A Wiring Diagram. USE COPPER SUPPLY WIRES. CN_PRESS_WH CN_JIG_PC(WH) FUSE_FAN1 250V T 3.15A Motor REACTOR_BLUE (up) FUSE_FAN2 250V T 3.15A CN_FAN2_BL CN_COMP Motor (down) L2_BR...
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MULTI F MAX WITH LGRED° MULTI WITH MULTI OUTDOOR UNIT Figure 17: KUMXA361A, KUMXA421A, and KUMXA481A Refrigerant Flow Diagram. Unit: Inch (mm) Ø3/8 (9.52) VI EEV Hotgas Valve Ø3/4 (19.05) Pressure Switch Table 28: KUMXA361A, KUMXA421A, and KUMXA481A PCB Connection Details.
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MULTI F MAX WITH LGRED° MULTI WITH MULTI OUTDOOR UNIT Sound Pressure Levels Figure 18: Acoustic Measurement Location. • • Measurements taken with no attenuation and units operating at full load normal operating condition. • Sound level will vary depending on a range of factors such as construction (acoustic absorption coefficient) of particular area in which the equipment is installed.
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MULTI F MAX WITH LGRED° MULTI WITH MULTI OUTDOOR UNIT Table 30: Sound Power Levels (dB[A]). Sound Power Levels Sound Power Levels (dB[A]) • Data is valid under diffuse field conditions. Model No. • Data is valid under nominal operating conditions.
MULTI F MAX BRANCH DISTRIBUTION UNIT PRODUCT DATA Mechanical Specifications on page 44 General Data on page 45 Dimensions on page 46 Wiring Diagram on page 47 Refrigerant Flow Diagram on page 48 Y-Branch Accessory on page 49 Branch Distribution Unit Orientation on page 50...
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Branch Distribution Unit. General Branch distribution units are designed for use with LG Multi F MAX or LG Multi F MAX with LGRED out- door units, and are internally piped, wired, assembled and run-tested at the factory. The branch distribu-...
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MULTI F MAX BRANCH MULTI WITH MULTI DISTRIBUTION UNIT Table 31: Multi F MAX Branch Distribution Unit General Data. Model Number PMBD3620ZR PMBD3630ZR PMBD3640ZR PMBD3641ZR No. of Connectable Indoor Units Ports A,B,C : 24,000 Max. Nominal Capacity / Port (Btu/h)
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MULTI F MAX BRANCH MULTI WITH MULTI DISTRIBUTION UNIT Figure 25: PMBD3620ZR, PMBD3630ZR, PMBD3640ZR, and PMBD3641ZR Wiring Diagram. Connect the indoor unit power supply wiring and communications wiring depending on the number installed. *Function is optional or factory installed depending on the model.
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MULTI F MAX BRANCH MULTI WITH MULTI DISTRIBUTION UNIT Figure 26: PMBD3620ZR, PMBD3630ZR, PMBD3640ZR, and PMBD3641ZR Refrigerant Flow Diagram. Main Vapor Piping (3/4 " [19.05mm]) Outdoor * PMBD3641ZR Unit Main Liquid D Vapor 1/2" (12.7mm) Piping D Vapor (3/8 " [9.52mm]) (3/8"...
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MULTI F MAX BRANCH MULTI WITH MULTI DISTRIBUTION UNIT No Substitutions on Piping Components Only LG supplied Y-branch can be used to join one pipe segment to two or more segments. applicable). Figure 27: LGRED Y-Branch Kits Branch Leg Straight-through Leg...
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Branch Distribution Unit Orientation Multi F MAX branch distribution (BD) units can be installed in a multitude of options to fit various building configurations and job or applica- tion requirements. Multi F MAX branch distribution units include electronic expansion valves that properly seat only if the branch distribution unit is installed in an acceptable orientation.
ELECTRICAL CONNECTIONS General Guidelines on page 52 Wiring Specifications on page 53 Systems for Multi F with LGRED on page 55 Systems for Multi F MAX with LGRED on page 56...
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LGRED Outdoor Unit Power Outdoor Unit Wiring. • Multi F and Multi F MAX LGRED systems operate at 1Ø, 208-230V, 60Hz, and power is wired to the Wiring outdoor unit only. • Power wiring to the outdoor unit(s) must be a minimum of: - 12 AWG, three (3) conductor for 18,000, 24,000, and 30,000 Btu/h Multi F with LGRED capacities.
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Multi F with LGRED Systems (Outdoor Unit to Indoor Units): • Power wiring must be a minimum of 14 AWG, three (3) conductor for 18,000, 24,000, 30,000 and 36,000 Btu/h Multi F capacities. • Communications wiring must be a minimum of 18 AWG, two (2) conductor for 18,000, 24,000, 30,000 and 36,000 Btu/h Multi F capacities.
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ELECTRICAL CONNECTIONS MULTI WITH MULTI Figure 38: Multi F with LGRED KUMXA181A, KUMXA241A, and KUMXA301A System Power Wiring and Communications Cable. CN_INPUT _BROWN CN_INPUT _BLUE BL OR Central GN/YL 3(A) 4(B) 3(A) 4(B) 3(A) 4(B) To Indoor Unit To Indoor Unit...
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ELECTRICAL CONNECTIONS MULTI WITH MULTI Figure 39: Multi F MAX with LGRED KUMXA181A, KUMXA241A, and KUMXA301A System Power Wiring and Communications Cable. L1_BR N1_BL BL OR Central L(L1) N(L2) L(L1) N(L2) L(L1) N(L2) 3(A) 4(B) L(L1) N(L2) 3(A) 4(B) L(L1) N(L2) L(L1) N(L2)
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• If using the LG Controller / Extension cable and the length needs to be extended, the LG Extension Kit (sold separately) must be used. A maximum of four (4) kits (up to 165 feet) can be used.
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Supplied For indoor units with CN-REMO connections: LG Supplied Group Control Kit (PZCWRCG3) Use one (or multiple) Group Control Kit(s) (sold separately) containing extension and Y-splitter cables. Use one (1) group control cable kit for each indoor unit in the group except for the last indoor unit.
PIPING LIMITATIONS AND PLACEMENT CONSIDERATIONS Piping Limitations on page 60 Selecting the Best Location for the Outdoor Unit on page 62 Outdoor Unit Clearance Requirements on page 65 Installing Outdoor Units Indoors on page 68 Branch Distribution Units on page 71...
MULTI Device Connection Limitations • The minimum number of connected and operating indoor units to Multi F / Multi F MAX with LGRED systems is two, taking into consider- ation the minimum combination ratio. • The maximum number of indoor units for each Multi F / Multi F MAX with LGRED heat pump system is:...
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PIPING LIMITATIONS MULTI WITH MULTI Example of a Multi F MAX with LGRED System with One Branch Distribution Unit Example: KUMXA361A outdoor unit with four (4) indoor units and one (1) branch distribution unit connected. ODU: Outdoor Unit. IDU: Indoor Unit.
PLACEMENT CONSIDERATIONS MULTI WITH MULTI Selecting the Best Location for the Outdoor Unit(s) DANGER • • • Select a location for installing the outdoor unit that will meet the following conditions: • • • • • Do Nots • • •...
PLACEMENT CONSIDERATIONS MULTI WITH MULTI Planning for Snow and Ice To ensure the outdoor unit operates properly, certain measures are required in locations where there is a possibility of heavy snowfall or severe windchill or cold: 1. Prepare for severe winter wind chills and heavy snowfall, even in areas of the country where these are unusual phenomena. 2.
PLACEMENT CONSIDERATIONS MULTI WITH MULTI Oceanside Applications Figure 45: Prevailing Wind Direc- Figure 46: Leeward Side of the tion. Building. Wind Protection If the outdoor unit is placed on a roof, position it with the compressor end (no coil surface) in the direction of the prevailing wind as shown Prevailing in the figure at right.
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Minimum Clearance Requirements for Multi F Single Fan Outdoor Units Specific clearance requirements in the diagram below are for single fan outdoor units. The figure below shows the overall minimum clear- ances that must be observed for safe operation and adequate airflow around the outdoor unit.
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MULTI WITH MULTI CONSIDERATIONS Minimum Clearance Requirements for Dual Fan Outdoor Units Figures below and on the next page illustrate clearance requirements for various installation scenarios for dual fan outdoor units. Use the hot isle / cold isle approach when placing multiple units in close proximity to each other. Outdoor unit fans draw air from the back of the unit and discharges out the front.
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MULTI WITH MULTI CONSIDERATIONS Minimum Clearance Requirements for Dual Fan Outdoor Units, Continued. • • Figure 53: Proper Outdoor Unit Placement and Clearances When There Are Obstacles on the Suction and the Discharge Sides. When Obstacle Height of the Discharge Side is Higher than the Outdoor Unit. Table 40: H, A, and L Ratio.
• Maintains coil heat transfer efficiency by reducing the number of and shortening the cycle time for defrost operation. • Easier maintenance and servicing during inclement weather. • When mounted in a fully enclosed space, limiting the ambient air temperature could allow the Multi F / Multi F MAX system designer to eliminate oversizing.
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PLACEMENT CONSIDERATIONS MULTI WITH MULTI Provide a means to drain the condensate generated during heating mode and defrost cycle in addition to rainwater that infiltrates the inlet louver enclosed area. • Install a field-provided drain pan under the outdoor units and provide a path to a nearby floor drain. •...
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PLACEMENT CONSIDERATIONS MULTI WITH MULTI Open Rate by Louver Radian Figure 56: Open Rate by Louver Radian Formula. ho = h * COS Total Area (A) = H * W Number of Open Spaces (N) = (Number of Louvers - 1) Effective Area (Af) = ho * W * N Louver Open Rate (n) = Af / A Af = A * n...
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PLACEMENT CONSIDERATIONS MULTI WITH MULTI Selecting the Best Location for the Indoor Units • • • • • Do Not’s • • • or Installation Manuals. Selecting the Best Location for the Branch Distribution (BD) Unit • • • • Do Not’s •...
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Branch Distribution Unit Orientation Multi F MAX branch distribution units can be installed in a multitude of options to fit various building configurations and job or application requirements. The installation location of the PCB within the branch distribution unit can be changed for easier service access, depending on the branch distribution unit installation itself.
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LG Electronics, U.S.A., Inc. Air Conditioning Technologies 4300 North Point Parkway Alpharetta, Georgia 30022 New Issue: EM_Multi_F-MAX_LGRED_ODU_R32_12_24 www.lghvac.com...
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