Air Cooled Condensers Operation and Installation Manual
General Safety Information Installation and maintenance are to be performed only by qualified personnel who are familiar with local codes and regulations, and are experienced with this type of equipment. Avoid contact with sharp edges and coil surfaces. They are a potential injury hazard. This equipment may contain a substance that harms public health and the environment. Venting certain refrigerants to the atmosphere is illegal. Refrigerant recovery devices must be used when installing or servicing this equipment. Consult local codes for requirements at your location. WARNING: There may be more than one source of electrical power supplied to this unit. Do not service before disconnecting all power sources. Inspection Check all items received against the bill of lading. The shipping receipt should not be signed until all items listed on the bill of lading are accounted for or noted on the shipping documents. Damaged material is the responsibility of the freight carrier and should not be returned to the manufacturer without prior approval. Carefully inspect all items for damage and immediately file a claim with the carrier. Heat transfer coils are leak tested, evacuated and shipped with a pressurized holding charge. Absence of this holding charge may indicate a leak has developed in transit. The system should not be charged with refrigerant until it is verified that there is no leak, or the source of the leak is located and repaired. Verify that the available electrical power supply is consistent with the voltage listed on the equipment nameplate. Power supply for 208/230 volt motors must be between 188 and 253 volts. Power supply for other motor voltages must be within +/- 10% of nameplate voltage. Phase imbalance must not exceed 2%. Unit Location The equipment is designed for outdoor installation and may be mounted on a roof or concrete slab. The units should be mounted level on roofs, slabs and/or structural supports that are sufficiently strong to support the total equipment operating weight. Consult with a professional engineer to determine safe mounting loads. Unrestricted airflow must be provided to each fan section of the equipment. The unit should be located far enough away from any wall or other obstruction to provide adequate clearance for ambient air inlet and discharge. Care must also be taken to avoid air recirculation from other nearby equipment. See Figure 1 for recommendations. Do not attach ductwork to the coil inlet or outlet. Locate the unit away from building air intakes and heat sources such as vents and exhaust fans. A corrosive environment, whether it comes from the jobsite or from another nearby source, will significantly shorten the service life of the coil and may require an appropriate coil coating or copper fins to extend the life of the unit. Equipment should be located away from occupied spaces to reduce the transmission of objectionable sound and/or vibration. Refrigerant piping should be sufficiently flexible to prevent transmission of noise and vibration into the building. Use isolation hangers to support refrigerant lines. The unit must be secured in its final location. Holes are provided in the mounting legs for this purpose. 2
Figure 1: Space and Location Requirements Note: Consideration should be given to allow ample space for maintenance work. Walls or Obstructions All sides of the unit should be a minimum of one overall unit width W away from any wall or barrier. Air Flow W Min. Multiple Units For units placed side by side, the minimum distance between the units is the overall width of the largest unit. If the units are placed end to end, the minimum distance between the units is 5 feet. Air Flow W Min. Air Flow Decorative Fences Fences must have 50% free area, with 1 foot of bottom clearance, and must not extend higher than the top of the unit. Units should be a minimum of one overall width W away from the fence. 12 Min. W Min. Air Flow W Min. Units in Pits The top of the unit must be level with, or higher than, the top of the pit. All sides of the unit should be a minimum of two overall unit widths 2W away from any wall of the pit. 2W Min. Air Flow 2W Min. 3
Rigging Instructions The equipment is designed to be lifted only by the lifting lugs installed on the unit. Use all available lifting lugs when rigging the unit. Always use a spreader bar that is at least as long as the distance between the furthest lifting lugs. See Figure 2 for recommended rigging and lifting procedure. Under no circumstances should the coil headers, return bends, or electrical box be used to lift or move this equipment. It is most convenient to install the unit mounting leg assemblies when the unit is in the horizontal position (fans facing upward) and supported by the rigging. The longer lifting lugs on one side of the unit (top side on shipping pallet) may be used temporarily to lift the unit off of the shipping pallet and lay horizontally on the ground. Figure 2 - Rigging Method Use all available lifting lugs. Always use spreader bar. Approximate Net Weights # Fans 800mm Single Wide Units 800mm Double Wide Units Weight (lbs.) # Lifting Lugs # Fans Weight (lbs.) # Lifting Lugs 1 550 4 4 1620 4 2 870 4 6 2200 4 3 1250 4 8 3000 4 4 1575 4 10 3880 8 5 1750 8 12 5100 10 6 2100 10 14 6000 10 7 2400 10 # Fans 500mm Double Wide Units Width (in.) Weight (lbs.) # Lifting Lugs 1 28.3 220 4 1 37.3 260 4 2 28.3 330 4 2 37.3 390 4 3 37.3 510 4 4
Unit Assembly and Installation The leg assemblies are shipped with the unit but not installed. All installation hardware is included with the leg assemblies. Install all supplied leg assemblies to the unit as shown in Figure 3. This is best accomplished while the unit is in the horizontal position on the rigging. Once the unit is set on its permanent base, each leg should be securely fastened to the base. Mounting holes are provided in the bottom of each leg for this purpose (hardware is not included with the unit). Figure 3 - Mounting Leg Installation Unit Cabinet 1/4 Hex Bolt 1/4 Flat Washer 4 Places Both Sides of Unit Mounting Leg Assembly Cross Brace Piping All jobsite refrigerant piping should conform to applicable local and state codes as well as the latest ANSI B9.1 and B31.5 standards and the ASHRAE 15-1992 Safety Code for Mechanical Refrigeration. Proper pipe sizing and following good commercial piping practices throughout the installation, including properly bracing the lines, are essential to proper system operation. Pipe sizing must always be determined using engineering calculations and never be based upon the inlet and outlet fittings on the condenser. This manual highlights only the most critical aspects of proper system piping. For more complete information, refer to the ASHRAE Handbook on Systems. Only AC&R type copper tubing should be used throughout the installation. Cut tubing with a wheel-type cutter, not a hacksaw. Debur before assembly in the fittings. If the tubing is not capped, clean the internal surface thoroughly with a clean, lint-free rag. Always clean tube and fitting areas that will be brazed with the proper grade of emery cloth. Soft solders are not to be used. Use a silver solder that contains sufficient silver content necessary for joint strength and flexibility, yet requires minimum use of flux. For copper to copper joints, use phos-copper solder with 15% silver content. Nitrogen should always be used to purge air from the piping during brazing to prevent copper oxide formations. Long horizontal lines should be avoided on rooftops. Generally, horizontal piping runs should slope slightly downward in the direction of flow. Provisions must be made to accommodate expansion and contraction of the lines, especially where the lines have long runs with few elbows or bends. The lines must also be supported at frequent intervals in accordance with good piping practice. 5
This is especially critical at the relatively weak condenser connections where all piping connected directly to the condenser must be supported as close to the condenser as possible. See Figure 4 for recommendations. Interconnecting piping of double wide units should be as short and direct as possible to the header connections. The inlet piping should always feed downward to the inlet header and be equipped with a pressure tap (purge) type valve at its highest point. The liquid outlet piping should be directed immediately downward in a minimum 15 drop leg to make a liquid seal. The drop leg must precede any bends or angles connecting it to the remainder of the liquid piping run. See Figure 4 for recommendations. Pressure/leak testing of the piping should be done as soon as the field piping has been completed. The high-side test pressure should never exceed the condenser nameplate rating. It is recommended that an electronic type leak detector be used to check for leaks at ALL joints, both field and factory. Prior to charging the system, a deep vacuum (triple evacuation recommended) must be drawn on the entire system to remove moisture and non-condensable gases. Install pressure transducers, if used, prior to evacuation. Replace all header and end turn covers that may have been removed to accommodate installation. Figure 4 - Unit Mounting and Piping * Denotes brace and clamp fastener of Interconnecting piping to condenser unit Concrete Pad Mounted * * Sizing a discharge line too small will result in a reduction of the systems capacity and an increase in compressor energy consumption. Sizing a discharge line too large will inhibit oil return to the compressor. The proper balance is to size discharge lines for approximately 4000 ft/min in vertical risers and 2000 ft/min in horizontal runs sloped downward in the direction of flow. See Figure 5 for guidance on discharge line sizing or consult the AHRAE Handbook on Systems for more detailed information. P traps should be installed at the base of all vertical risers and every 15 feet up the riser. These traps should be formed from short radius street ells. Special consideration must be given to vertical risers when the refrigeration system undergoes wide swings in load and/or the compressor system employs significant capacity modulation capabilities (eg. Parallel rack). In these cases a double riser should be used as shown in Figure 6. 6
Note: If isolation valves are used to shut down half of the condenser during winter operation, precautions must be taken to eliminate thermal shock when the valves are opened for warmer weather operation. Isolation valves must not be supported from or by the condenser headers. Figure 5 - Line Sizing Guide Line Size Capacities in Tons Discharge Line Line Size Liquid LIne R-404A Sat. Suction R-507 Sat. Suction R-410A Sat. Suction Type L Copper 100 FPM Refrigerant Velocity Temp F Temp F Temp F OD (inches) -40 0 40-40 0 0-40 0 40 R-404A R-507 R-410A 1/2 0.61 0.70 0.79 0.60 0.70 0.79 1.2 1.3 1.3 1.3 1.3 2.0 5/8 1.1 1.3 1.5 1.1 1.3 1.5 2.2 2.4 2.5 2.1 2.0 3.2 3/4 1.9 2.2 2.5 1.9 2.2 2.5 3.7 4.0 4.2 3.1 3.0 4.7 7/8 3.0 3.4 3.9 3.0 3.5 3.9 5.8 6.2 6.5 4.4 4.2 6.7 1-1/8 6.0 7.0 7.8 6.0 7.0 7.8 11.6 12.5 13.2 7.5 7.2 11.4 1-3/8 10.5 12.1 13.6 10.4 12.1 13.6 20.2 21.7 22.9 11.4 11.0 17.4 1-5/8 16.5 19.1 21.4 16.4 19.1 21.5 31.9 34.3 36.1 16.1 15.6 24.6 2-1/8 34.1 39.4 44.3 33.9 39.4 44.4 65.9 70.8 74.6 28.0 27.1 42.8 2-5/8 60.0 69.4 77.9 59.7 69.4 78.2 115.9 124.5 131.2 43.2 41.8 66.0 3-1/8 95.5 110.5 124.0 95.0 110.4 124.3 184.6 198.4 209.0 61.7 59.6 94.2 3-5/8 141.5 163.7 183.7 141.0 163.9 184.5 273.5 293.9 309.6 83.5 80.6 127.4 4-1/8 199.0 230.4 258.6 198.5 230.7 259.7 385.1 413.8 435.9 108.5 104.8 165.7 Source: ASHRAE Refrigeration Handbook: a) Line size capacities based on pressure drop equivalent to 1 feet. b) Values in table are based on 105 F condensing temperature. Multiply table values by Condensing Temperature Factors for other condensing temperatures. c) Extreme subcooling and/or line lengths may vary line sizing calculations. Condensing Temperature Factors Cond. Discharge Line Temp F R-404A R-507 R-410A 80 0.870 0.873 0.815 90 0.922 0.924 0.889 100 0.974 0.975 0.963 110 1.009 1.005 1.032 120 1.026 1.014 1.096 130 1.043 1.024 1.160 Sizing a liquid line too small can result in a complete loss of subcooling and malfunctioning of the expansion valve. Oversizing the liquid line can negatively impact the oil-to-refrigerant ratio as well as increasing the amount of refrigerant needed to charge the system. The proper balance here is to size the liquid line such that refrigerant velocity does not exceed 100 ft/ min.. See Figure 5 for guidelines or consult the ASHRAE Handbook for more detail. Liquid lines must be installed so that they are free draining to the receiver, absent of any traps or loops. It is best to pipe liquid lines so there is an immediate 2 to 3 feet drop at the condenser outlet before any field headering, ells, or horizontal runs. Horizontal runs on rooftops should be minimized and slope downward in the direction of flow. 7
P Trap Design Figure 6 - P Trap and Double Riser Design Pitch Condenser Discharge Line Liquid Line Pitch Receiver Trap Compressor Double Riser Design Pitch Riser A sized for minimum load condition. Riser B sized so that the combined cross sectional area of both risers equal the cross sectional area of a single riser properly sized for full load conditions. Condenser Discharge Line B Discharge Line A Liquid Line Pitch Receiver Trap Compressor Electrical Wiring The unit is equipped with an electrical power disconnect switch that must be turned off before any electrical work is performed on the unit. Electric installation and maintenance should be performed only by a qualified electrician and in accordance with the National Electrical Code, local codes and regulations. Proper overcurrent protection should be provided for all fan motors. WARNING: There may be more than one source of electrical current to this unit. Do not service before disconnecting all power supplies. Power supply voltage, phase, and frequency must match specifications shown on the unit nameplate. Always check motors for proper rotation. Standard 1 and 3 phase motors contain an internal thermal overload protection (TOP) switch that must be wired to the motor contactor holding coil to properly protect the motor from overheating (see wiring diagram for proper installation). The TOP is limited to 1.6 amps maximum inrush current. For 115 and 230 VAC control circuits, a motor 8
contactor holding coil with 60 VA maximum inrush current is recommended. For 24 VAC control circuits, a motor contactor holding coil with 12 VA maximum inrush current, or use of a pilot relay, is recommended. Standard 3 phase motors are dual voltage and may be quickly converted in the field by repositioning the jumpers at the motor terminal block (See Figure 7). Variable speed EC motors are single voltage and contain internal overload protection, under voltage protection, and phase imbalance protection. These motors do not require the use of a contactor. Electrical leads from each motor terminate at a common terminal block in the electrical panel. Where fan cycle controls are furnished and factory installed, the motors and TOPs are completely wired to the contactors and control circuits (See Figure 8). The motors should be checked for proper voltage and rotation. Figure 7 - Motor Terminal Block Arrangements 230 VAC Jumpers Standard 3 Phase Capacitor Standard 1 Phase U1 V1 W1 W2 U2 V2 TOP TOP U1 Z U2 TOP TOP L1 L2 L3 460 V Jumpers Control Circuit GR L N GR Control Circuit 800 Variable Speed EC 500 Variable Speed EC RSA RSB GND Ain 1U HOV Ain 1I Din 1 NO COM NC PE L1 L2 L3 +24V +10V D1 E1 11 14 L1 L2 L3 1 2 yellow 3 4 yellow/red 5 Com A1 0-10 VDC Speed Control 6 7 1 2 3 GR 1 2 3 L1 L2 L3 yellow yellow/red Com A1 0-10 VDC Speed Control L1 L2 L3 GR 9
Figure 8A - Typical Wiring Diagram with Individual Contactors M FAN MOTOR C CONTACTOR F FUSE TB TERMINAL BLOCK MP MOTOR PROTECTOR FCR FAN CYCLE (RELAY) FCA FAN CYCLE (ANALOG) FCPM FAN CYCLE POWER MODULE DS DISCONNECT SWITCH FAN MOTOR IDENTIFICATION M7 M6 M5 M4 M3 M2 M1 HEADER END NOTE: ALWAYS WIRE FCRs TO NORMALLY OPEN TERMINAL AND PROGRAM THE SENSOR FAILURE MODE TO ON. Figure 8B - Typical Wiring Diagram with Paired Motor Contactors M FAN MOTOR C CONTACTOR F FUSE TB TERMINAL BLOCK MP MOTOR PROTECTOR FCR FAN CYCLE (RELAY) FCA FAN CYCLE (ANALOG) FCPM FAN CYCLE POWER MODULE DS DISCONNECT SWITCH FAN MOTOR IDENTIFICATION M14 M12 M10 M8 M6 M4 M2 M13 M11 M9 M7 M5 M3 M1 HEADER END NOTE: ALWAYS WIRE FCRs TO NORMALLY OPEN TERMINAL AND PROGRAM THE SENSOR FAILURE MODE TO ON. 10
Figure 8C - Typical Wiring Diagram with Variable Speed Header Fans M FAN MOTOR C CONTACTOR F FUSE TB TERMINAL BLOCK MP MOTOR PROTECTOR FCR FAN CYCLE (RELAY) FCA FAN CYCLE (ANALOG) FCPM FAN CYCLE POWER MODULE DS DISCONNECT SWITCH FAN MOTOR IDENTIFICATION M7 M6 M5 M4 M3 M2 M1 HEADER END M FAN MOTOR C CONTACTOR F FUSE TB TERMINAL BLOCK MP MOTOR PROTECTOR FCR FAN CYCLE (RELAY) FCA FAN CYCLE (ANALOG) FCPM FAN CYCLE POWER MODULE DS DISCONNECT SWITCH Figure 8D - Typical Wiring Diagram with VSEC Fan Motors FAN MOTOR IDENTIFICATION M7 M6 M5 M4 M3 M2 M1 HEADER END 11
To assure a long service life of the fan motors, it is essential that the motor terminal box covers, conduits, and conduit connectors be properly installed. Each of these components are supplied with seals and gaskets that will keep the motor wiring and connections dry when maintained in good condition. If a seal or gasket is damaged, replace it immediately. The use of caulk or other sealants is not an acceptable means of repairing these components! AC MOTOR VARIABLE SPEED EC MOTOR TIGHTEN 4 SCREWS IN CRISS-CROSS PATTERN TO 2.5 ft.-lb. TIGHTEN 2 SCREWS TO 0.6 ft.-lb. TIGHTEN CONDUIT FITTING TO 1.5 ft.-lb. ASSURE THAT GASKET IS INSTALLED AND IN GOOD CONDITION ASSURE THAT SEAL IS PROPERLY INSTALLED IN CONDUIT FITTING TIGHTEN CONDUIT FITTING TO 3.0 ft.-lb. ASSURE THAT O-RING IS SEALED RADIALLY ON TERMINAL BOX ASSURE THAT SEAL IS PROPERLY INSTALLED IN CONDUIT FITTING ASSURE THAT SNAP RING IS FIRMLY INSTALLED IN CONDUIT FITTING Figure 9 - Control Circuit Transformer Wiring Factory supplied control circuit transformers for 208-230 volt models are factory wired for 230 volt primary supply voltage. If actual supply voltage is 208 volts, move wire from terminal H3 to terminal H2 on the primary side of the transformer (see Figure 9). H1 H2 H3 H4 Primary Input Voltage Terminals 208 H1 & H2 230 H1 & H3 460 H1 & H4 Secondary Output Head Pressure Control Operating pressure in an air-cooled condenser (head pressure) varies proportionally with ambient temperature. A properly sized, installed, and maintained air-cooled condenser will operate safely at the higher head pressures associated with the higher ambient temperatures during the summertime. At lower ambient conditions, however, precautions must be taken to assure that sufficient head pressure is maintained to assure proper operation of the thermal expansion valve(s). For many systems, this lower limit on head pressure corresponds with an ambient temperature of roughly 60 F. The specific lower head pressure limit (and corresponding lower ambient temperature limit) for any system may only be determined through a thorough review of the pressure requirements for the complete system under consideration. Whenever the condenser is anticipated to operate at ambient temperatures below the minimum limit, additional head pressure control will be required. 12
Fan Cycling Cycling condenser fans on and off provides an automatic means of maintaining head pressure at lower ambient temperatures. Fan cycling controls activate either from an ambient air temperature sensor or a condenser pressure sensor. Ambient fan cycle controls are most appropriate for condensers with multiple circuits or in milder climates. Pressure fan cycle controls are most appropriate in colder climates, systems designed with multiple compressors or stages of unloading, or systems incorporating heat reclaim or hot gas defrost. When fan cycling is ordered from the factory, the pressure transducer or temperature sensor is shipped loose in the electrical panel and must be field installed prior to system start-up. Pressure transducers are screwed into the schrader valve located in the liquid header of the coil. Temperature sensors are hung 4 inches below the center of the coil using a nylon wire tie. Holes are provided at each intermediate tube sheet for this purpose. Sensors are then wired to the provided fan cycle controller as shown below: Sn 2 Temperature Sensor 24V C C Sn 3 White Sn 1 5V C Black Red Pressure Transducer Ambient fan cycling has limits as shown in Figure 10. Where operation of the condenser is anticipated to occur outside of these limits, additional forms of head pressure control will be required. In these cases, pressure fan cycling, condenser flooding and/or variable speed motors should be considered. With any type of fan cycle control, great care must be taken by the installer in making adjustments to prevent short cycling of the fans. Any fan cycle that is less than 3 minutes is considered short cycling and will be detrimental to the system performance and life cycle. Short cycling is most often caused by setting the differential or set points on the controller too close. Recommended differential settings for ambient fan cycle controls are 5 F and a minimum of 35 PSIG differential for pressure controls. Figure 11 provides guidelines for control settings. All systems and operating conditions vary and the controls may require further refinement of these settings in the field to provide optimum system performance and prevent short cycling. The fan, or set of fans for a double wide units, closest to the headers should never be cycled for head pressure control. They should operate continuously whenever a compressor is turned on. Always set the headers fan(s) to be first on and last off. Never cycle more than one fan at a time on single wide units. Never cycle more than 2 adjacent fans (one on each side) at a time on double wide units. Figure 10 - Minimum Ambient Temperature for Ambient Fan Cycling Number of Design TD F Fans Long 10 15 20 25 30 2 70 60 55 45 35 3 65 55 40 30 15 4 60 45 30 15 0 5 55 35 20 10 0 6 50 30 10 0 0 7 50 30 10 0 0 13
Figure 11 - Fan Cycling Control Settings Header End M1 M3 M5 M7 M9 M11 M13 M2 M4 M6 M8 M10 M12 M14 Stage --- 1 2 3 4 5 6 Contactor C1 C2 C3 C4 C5 C6 C7 # Fans Long Always On On Off On Off On Off On Off On Off On Off Temperature Control ( F) 2 70 65 3 70 65 80 75 4 70 65 75 70 80 75 5 70 65 75 70 80 75 85 80 6 70 65 75 70 80 75 85 80 90 85 7 70 65 75 70 80 75 85 80 90 85 95 90 R-404A Pressure Control (PSIG) 2 220 185 3 220 185 245 210 4 220 185 235 200 250 215 5 220 185 235 200 250 215 260 225 6 220 185 235 200 245 210 255 220 265 230 7 220 185 235 200 245 210 255 220 265 230 270 235 R-410A Pressure Control (PSIG) 2 300 255 3 300 255 330 285 4 300 255 320 275 335 290 5 300 255 320 275 335 290 350 305 6 300 255 320 275 335 290 350 305 360 315 7 300 255 320 275 335 290 350 305 360 315 365 320 R-134a Pressure Control (PSIG) 2 115 90 3 115 90 130 105 4 115 90 125 100 135 110 5 115 90 125 100 135 110 140 115 6 115 90 125 100 130 105 135 110 140 115 7 115 90 125 100 130 105 135 110 140 115 145 120 Note: Motor contactor to be wired to "NO" contact of fan cycle control. 14
Variable Speed EC Fan Motors (VSEC) VSEC fan motors offer the opportunity for ultra-high energy efficiency, extremely quiet operaion and precise head pressure control. These three phase motors will operate in the range of 10% to 100% of their full speed rating in response to a 1 to 10 VDC proportional signal supplied by a pressure transducer and speed controller. Head pressure is controlled by speeding up and slowing down the fans causing air flow across the coil to increase and decrease. Luvata VSEC fan motors are controlled under the following specifications: 800mm Fans 500mm Fans motor turns off < 1.0 VDC < 0.8 VDC motor operates at 10% of full speed 1.0 VDC 1.0 VDC motor restarts after falling below minimum voltage > 1.5 VDC > 1.1 VDC motor operates at 100% of full speed 10.0 VDC 10.0 VDC Header fans should never be allowed to turn off any time a compressor is running. It is recommended that header fans always receive a minimum control voltage of 1.1 VDC. Down stream fan motors may be allowed to turn off by allowing control voltage to drop below 0.8 VDC. VSEC Header Fan Control VSEC Non-Header Fan Control 10.0 Control Voltage (VDC) 1.1 Proportional Range 100% 11% Fan Speed (% of full speed) 10.0 Control Voltage (VDC) 0.8 Proportional Range 100% 10% Fan Speed (% of full speed) Set Point End Point Pressure Settings (PSIG) LCV models are equipped with all VSEC fan motors, providing the ultimate in control technology. All fans are ramped up and down in speed together. Header fans will always operate at a minimum of 11% of full speed while downstream fans are allowed to turn off. LCS and LCU models are available with VSEC header fans where the remaining of downstream fans are standard single speed fans that may be equipped with on/off pressure fan cycling. As downstream fans cycle on/off, the VSEC header fans ramp up/down in speed to more precisely control head pressure. Header fans will always operate at a minimum 11% of full speed. See Figure 12 for recommended speed control settings for VSEC fan motors. 0% Pressure Settings (PSIG) In addition to variable speed operation, Luvata VSEC fan motors include many advanced technology features including inherent overheating protection, phase loss protection, over/under voltage protection, and rotation correction (regardless how they are wired, they always rotate the correct direction). WARNING: Variable speed EC fan motors may retain voltage even after power has been disconnected. Wait 5 minutes after disconnecting power before touching any conductors connected to variable speed EC fan motors. Set Point End Point 0% 15
Figure 12 - Speed Control Settings for VSEC Fans Refrigerant Set Point (PSIG) Header Fans End Point (PSIG) Set Point (PSIG) Downstream Fans End Point (PSIG) R-404A 165 260 160 260 R-410A 220 365 215 365 R-143a 78 145 75 145 For on/off cycling of single speed downstream fans, use settings shown in Figrure 11. Splitting Controls Additional head pressure control can be achieved by valving off a portion of the condenser circuit and removing that portion from the refrigeration circuit. In addition to providing a means of head pressure control, this control will reduce the amount of refrigerant required to operate the condenser with flooded head pressure controls. Condenser splitting should be set up as a seasonal adjustment controlled by ambient temperature. An initial setting of 50 F with a 20 F differential is recommended. For double wide condensers, it is recommended to shut off the fans on the isolated side of the condenser to save energy. Splitting is not a substitute for fan cycling but, rather, an addition to it. Splitting is best used in conjunction with pressure fan cycling. Flooding Head Pressure Controls Flooding controls are recommended for air-cooled condensers operating in low ambient temperatures beyond the limits of fan cycling controls or under low load conditions. These controls require additional refrigerant be added to the system to flood the condenser with liquid refrigerant. This additional amount of refrigerant can often be reduced by using flooding controls in conjunction with fan cycling and/or splitting. Several styles of flooding valves are available. If not supplied with the equipment, contact the valve manufacturer for specific recommendations. Refrigerant Charge The total summer design refrigerant charge necessary for proper system operation is the sum of the charges needed for the evaporator(s), refrigerant piping, condenser and receiver. The summer design charge required for the condenser is listed in Figure 13 for R-404A. For alternate refrigerants, multiply the values in Figure 13 by the factors shown. When using low ambient flooding controls, the Additional Refrigerant Charge listed in Figure 13 must be added to the Summer Charge to determine the total condenser refrigerant charge required for proper operation. Note that the Additional Refrigerant Charge is dependent upon the design TD for the condenser and must be multiplied by the factors listed in Figure 14 for TDs other than 20 F. Multiply the Additional Refrigerant Charge by the factors shown for refrigerants other than R-404A. 16
Figure 13 - Refrigerant Charge for Condensers Models *= 0-10 FPI, 8-8 FPI, 2-12 FPI Summer Refrigerant Charge Additional Refrigerant Charge Required for Flooded Condenser Operation Lbs. R-404A @ 20 F TD) Minimum Ambient Temperature ( F) LCS8* LCU8* LCV8* (Lbs. R-404A) +60 +40 +20 0-20 11-007 11-005 11-007 10 5 6 6 7 7 11-009 11-006 11-009 13 7 8 8 9 9 12-011 12-008 12-012 12 6 7 7 8 9 12-015 12-101 12-015 18 9 11 11 13 13 12-018 12-012 12-018 23 14 16 15 18 18 13-022 13-016 13-023 32 32 35 36 39 41 13-026 13-018 13-027 43 42 46 48 52 54 14-030 14-021 14-030 43 42 46 48 52 54 14-035 14-023 14-036 56 58 63 65 70 73 15-040 15-027 15-041 94 102 109 119 124 131 15-046 15-030 15-047 127 134 144 157 163 173 16-054 16-036 16-056 153 160 172 188 195 207 17-062 17-042 17-064 178 187 201 219 228 242 22-022 22-015 22-022 22 12 14 14 16 17 22-029 22-020 22-029 33 18 21 21 24 25 22-035 22-023 22-035 44 25 28 28 33 33 23-044 23-031 23-045 60 61 67 69 75 78 23-052 23-036 23-053 81 80 88 91 99 102 24-060 24-041 24-060 81 80 87 91 98 102 24-070 24-048 24-071 108 107 116 121 131 136 25-081 25-053 25-080 181 190 203 222 231 245 25-091 25-059 25-092 248 246 265 289 301 319 26-107 26-069 26-108 293 300 322 351 366 387 27-123 27-082 27-125 349 342 367 401 418 444 LCS5* LCV5* 11-008 1.1 0.6 0.7 0.7 0.8 0.8 11-013 2.3 1.1 1.3 1.3 1.5 1.6 11-018 3.4 1.8 2.0 2.0 2.4 2.4 11-024 11-024 3.0 1.5 1.7 1.7 2.0 2.1 11-032 11-033 4.4 2.3 2.7 2.7 3.1 3.2 11-039 11-039 5.9 3.1 3.6 3.5 4.1 4.2 12-051 12-051 6.4 3.8 4.3 4.3 5.0 5.0 12-063 12-063 8.6 5.0 5.7 5.7 6.6 6.7 12-067 12-069 9.2 4.8 5.6 5.5 6.5 6.6 12-079 12-081 12.3 6.4 7.4 7.4 8.6 8.8 13-099 13-100 13.0 6.9 7.9 7.9 9.2 9.3 13-113 13-114 17.4 9.1 10.5 10.4 12.2 12.4 17
Figures 14 - Flooded Charge Adjustment Factors for Alternate Conditions Start-Up Prior to start-up the following items should be checked: Fans rotate freely. Motors and mounts are securely fastened. Legs are securely attached to the unit and to the mounting structure. Remove debris from around the unit that could potentially blow airflow through the coil. Upon start-up the following items should be checked: Fans are rotating in the proper direction airflow should pass through the coil first, then through the fan and away from the unit. High pitched noise and/or excessive vibration in the discharge line is likely caused by compressor pulsation. Install a discharge baffle (available from compressor manufacturer) or a discharge line muffler at the compressor discharge to correct. Maintenance Air-cooled condensers require little maintenance but regular performance of these items are critical for extended service life and peak performance. WARNING : Disconnect all power sources to the unit before performing any electrical work on the unit or working near the fans. 18 Refrigerant Capacity Factors Refrigerant Factor R-507 1.035 R-410A 1.026 R-134a 1.088 Design Minimum Ambient Temperature ( F) TD ( F) 60 40 20 0-20 10 2.46 1.4 1.25 1.16 1.13 15 1.74 1.19 1.13 1.07 1.05 20 1 1 1 1 1 25 0.38 0.8 0.88 0.91 0.93 30 ---- 0.59 0.76 0.84 0.88 Clean the coil fins every 6 months or more frequently in severe conditions. This may be accomplished brushing and vacuuming or by applying a commercially available coil cleaner specifically developed for cleaning copper and/or aluminum coils. Never use acid-based cleaners. Always follow label directions. Remove any debris trapped between the coil and fans. Comb bent coil fins. Tighten all electrical connections. Tighten fasteners connecting the motors to their mounts, motor mounts to the unit, legs to the unit and the mounting structure. Service Replacement Parts The fan, motor and guard are provided as a single assembly. Models RPM Diameter (In.) Voltage Part Number LCS5011-008/013/018 750 19.7 208-230/1/60 114979200 LCS5 All Other 1 Phase 1400 19.7 208-230/1/60 114979100 LCS5 All 3 Phase 1550 19.7 208-230-460/3/60 114979000 LCV5 VSEC 19.7 208-230/3/60 114979400 LCV5 VSEC 19.7 460/3/60 114979300 LCS8 All 3 Phase 1100 31.5 208-230-460/3/60 114699800 LCU8 All 3 Phase 500 31.5 208-230-460/3/60 114978700 LCV8 VSEC 31.5 208-230/3/60 114978900 LCV8 VSEC 31.5 460/3/60 114978800
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Luvata Grenada LLC Commercial Refrigeration Products PO Box 948 / 3984 Highway 51 South Grenada, MS 38902-0948 Tel: 800-993-2579 / Fax: 662-229-2002 Email: comref@luvata.com Web: www.luvata.com www.luvata.com Part # 114989600 Printed in the USA June 2011