Installation, Start-Up and Service Instructions

Transcription

1 39NC Curb-Mounted Central Station Air-Handling Units Installation, Start-Up and Service Instructions This air-handling equipment is designed to provide safe and reliable service when installed correctly and operated within design specifications. To avoid injury to personnel and damage to equipment or property when operating this equipment, use good judgment and follow safe practices as outlined below. NEVER enter an enclosed fan cabinet or reach into a unit while the fan is running. LOCK OPEN AND TAG the fan motor power disconnect switch before working on a fan. Take fuses with you and note removal on tag. CHECK the assembly and component weights to be sure that the rigging equipment can handle them safely. Note, also, the centers of gravity and any specific rigging instructions. CHECK for adequate ventilation so that fumes will not migrate through ductwork to occupied spaces when welding or cutting inside air-handling unit cabinet or plenum. WHEN STEAM CLEANING COILS be sure that the area is clear of personnel. DO NOT remove access panel fasteners until fan is completely stopped. Pressure developed by a moving fan can cause excessive force against the panel and toward personnel. DO NOT work on dampers until their operators are disconnected. BE SURE that fans are properly grounded before working on them. SAFETY CONSIDERATIONS SECURE drive sheaves with a rope or strap before working on a fan to ensure that rotor cannot free-wheel. DO NOT restore power to unit until all temporary walkways inside components have been removed. NEVER pressurize equipment in excess of specified test pressures. PROTECT adjacent flammable material when welding or flame cutting. Have a fire extinguisher at hand and ready for immediate use. If unit is installed on a curb open to the inside of the building, have a fire extinguisher ready for immediate use inside the building under the unit. PREVENT unauthorized entry into the unit; leave safety latches in place on access doors except during installation or service procedures. After accessing a section, replace and tighten the safety latch. FIELD supplied motors should be Underwriters Laboratories (UL) or Canadian Standards Association (CSA) approved. FIELD wiring must comply with National Electrical Code (NEC) and all local requirements. DO NOT destroy watertight integrity by fastening electrical conduit, disconnects, or other hardware to the unit with screws that pierce the exterior cabinet. Both exterior and bottom panels are watertight. Use conduit standpipes in fan section(s) to route wiring into the unit from the interior space below. Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations. Book 3 PC 201 Catalog No Printed in U.S.A. Form 39NC-1SI 3-97 Pg 1 Replaces: New Tab 1b

2 CONTENTS Page SAFETY CONSIDERATIONS...1 INTRODUCTION...2 UNIT AND COMPONENT IDENTIFICATION PHYSICAL DATA PREINSTALLATION Inspection...10 Rigging...10 Long-Term Storage...10 Service Clearance...10 Internal Vibration Isolation...19 Roof Curb...19 Pier or Beam Mount...19 INSTALLATION Rigging...22 Sheet Metal Duct Connections...23 Doors...26 Intake Rain Hoods...26 Wiring...26 Fan Motors and Drives...26 Sheaves...28 V-Belts...29 Inlet Guide Vane Actuators, Forward-Curved Fans...30 Inlet Guide Vane Actuators, Airfoil Fans...31 Damper Actuators...32 Water and Steam Coil Piping Recommendations...34 Coil Freeze-Up Protection...35 Refrigerant Piping, Direct-Expansion Coils...35 Condensate Drain...52 START-UP Checklist...53 SERVICE General...55 Fan Motor Replacement...55 Cleaning Double-Wall Interiors...55 Coil Cleaning...55 Winter Shutdown...55 Coil Removal...55 Changing Coil Hand...58 Filters...58 Intake Hood Demisters...69 Fan Shaft Bearing Removal...70 Fan and Shaft Removal...70 Lubrication...70 Drive Package Data METRIC CONVERSION CHART...74 INTRODUCTION Carrier 39NC Series air-handling units are designed specifically for outdoor installation. The units have sloped tops, watertight cabinets, and specially designed base rails that ensure a tight seal with a curb. Each unit is factory assembled and shipped as a completely integrated package. The 39NC Series units are available for 2 basic duct arrangements. In the first arrangement, the fan discharge is directly attached to the supply duct, which is exposed for a distance before the duct penetrates the roof into the building. This arrangement can be installed either on a roof curb or on a pier. In the second type of duct arrangement, the fan discharges into a factory supplied plenum. The plenum (DPL1) has an opening at the bottom where supply air ductwork can be attached; the supply duct is confined within the curb. This arrangement must be curb mounted. UNIT AND COMPONENT IDENTIFICATION All 39NC component codes are listed and described in Table 1. Each component code has a 3-digit letter prefix that describes the basic component type; a fourth numerical digit indicates the variant for a given type of section. Components are assembled into an integrated unit at the factory. See Fig. 1 for an example of a unit label showing the model number and components in a typical assembled unit. The 39NC units are configured for blow-thru or drawthru operation. Return fan arrangements are also available. See Fig. 2-4 for unit component arrangements for each configuration. Fig. 1 Unit Identification Label 2

3 Table 1 39NC Component Code Definitions COMPONENT CODE ACC1 ACC2 AFS3 AFS5 AMX1 ANG1 BCC2 BCF1 BCF2 BCS7 BPH1 BPH2 CDC1 CDC2 CIC1 CIC2 CIC3 DIF2 DPL1 EMB1 FBP1 FCS3 FCS5 FLT1 DESCRIPTION Access Section (Upstream Location) Access Section (Downstream Location) Airfoil Fan Section, Horizontal Draw Thru Airfoil Fan Section, Blow-Thru Air Mixer Section Angle Filter Section Bypass Cooling Coil Section Bag/Cartridge Filter Section (Upstream Location, 2-in. Prefilters) Bag/Cartridge Filter Section (Downstream Location, 2-in. Prefilters) Blow-Thru Cooling Coil Section (Downstream Location) Bypass Heating Coil Section Bypass Heating Coil Section (Extended Length) Curb Discharge Component (Blank End Cap) Curb Discharge Component (Discharge Duct Connection) Curb Inlet Component (Blank End Cap) Curb Inlet Component (Horizontal Inlet Duct Connection) Curb Inlet Component (Outside Air Intake with Hood) Diffuser Section (Downstream Location) Downblast Plenum Section (Bottom Discharge) Exhaust and Mixing Box (Side Exhaust with Opposite-Side Outdoor-Air Intake) Face and Bypass Damper Section Forward-Curved Fan Section, Horizontal Draw-Thru (07-61 Sizes Only) Forward-Curved Fan Section, Blow-Thru (07-61 Sizes Only) Flat Filter Section COMPONENT CODE FMB4 HRS1 LCS1 LCS2 LCS3 MCS1 MCS2 MCS3 MHS1 MXB4 MXB7 PLN1 PLN2 PLN6 RAF1 RAF2 RFC1 RFC2 SHS1 DESCRIPTION Combination Filter Mixing Box (Bottom and Rear Inlet) Heat Reclaim Section Large Cooling Coil Section Large Cooling Coil Section With Extended Drain Pan (Upstream Humidifier Mount) (07-26 Sizes Only) Large Cooling Coil Section With Extended Drain Pan (Downstream Humidifier Mount) (07-26 Sizes Only) Medium Cooling Coil Section Medium Cooling Coil Section With Extended Drain Pan (Upstream Humidifier Mount) Medium Cooling Coil Section With Extended Drain Pan (Downstream Humidifier Mount) Medium Heating Coil Section (uses large face area coil in sizes, medium face area coil in sizes) Mixing Box (Bottom and Rear Inlet) Mixing Box (Rear Inlet Only) Short Plenum Section (Upstream Location) Long Plenum Section (Upstream Location) Short Plenum Section (Downstream Location) Return-Air Airfoil Fan Section (Bottom Inlet) Return-Air Airfoil Fan Section (Rear Inlet) Return-Air Forward-Curved Fan Section (Bottom Inlet) (07-61 Sizes Only) Return-Air Forward-Curved Fan Section (Rear Inlet) (07-61 Sizes Only) Small Heating Coil Section (uses bypass face area coil in all unit sizes) NOTE: Components are not available for individual shipment. All components must be ordered for factory assembly into integrated units. 3

4 WITHOUT FACE AND BYPASS WITH FACE AND BYPASS NOTES: 1. If first component in airstream is a coil or filter section, PLN2 or ACC1 must be immediately upstream. 2. BCF1 accepts bag filters up to 12-in. long. When longer filters are used, one or more plenum sections (PLN1) must be ordered. Each PLN1 section provides 8 in. of additional clearance. 3. Two coils on 61 size and larger units. 4. Two coils on 92 size unit. 5. Two coils on sizes Not available on sizes ACC1 required before FBP1 for service access. 8. When DPL1 and CDC1 are added downstream, static pressure correction factor applies to fan performance. See Fan Performance section in Product Data catalog. Fig. 2 Unit Section Arrangements, Horizontal Draw-Thru Units 4

5 Typical draw-thru components as shown in Fig. 2 may be used upstream of fan section NOTES: 1. Two cooling coils on 61 and larger units. 2. BCF2 accepts bag filters up to 12-in. long. When longer filters are used, one or more plenum sections (PLN6) must be ordered. Each PLN6 section provides 8 in. of additional clearance. Fig. 3 Unit Section Arrangements, Blow-Thru Units Fig. 4 Unit Section Arrangements, Return Fan 5

6 PHYSICAL DATA Data describing the physical properties of 39NC coils and fans is provided in Tables Table 2 Coil Physical Data 39NC UNIT SIZE CHILLED WATER/ DIRECT EXPANSION Large Face Area Nominal Capacity (cfm) at 550 fpm ,894 11,440 14,214 Size (Length x Width) (in.) x x x x x x x Total Face Area (sq ft) Medium Face Area Nominal Capacity (cfm) at 550 fpm ,989 9,421 11,970 Size (Length x Width) (in.) x x x x x x x40 Total Face Area (sq ft) Bypass (Chilled Water Only) Nominal Capacity (cfm) at 550 fpm ,989 9,421 11,970 Size (Length x Width) (in.) x x x x x x x40 Total Face Area (sq ft) HOT WATER HEATING Large Face Area Nominal Capacity (cfm) at 700 fpm ,320 14,559 18,090 Size (Length x Width) (in.) x x x x x x x Total Face Area (sq ft) Bypass Nominal Capacity (cfm) at 700 fpm ,894 11,990 15,234 Size (Length x Width) (in.) x x x x x x x40 Total Face Area (sq ft) STEAM HEATING COIL Large Face Area Nominal Capacity (cfm) at 700 fpm ,673 14,388 17,138 Size (Length x Width) (in.) x x x x x x x45 Total Face Area (sq ft) Bypass Nominal Capacity (cfm) at 700 fpm ,762 11,305 14,853 Size (Length x Width) (in.) x x x x x x x39 Total Face Area (sq ft)

7 Table 2 Coil Physical Data (cont) 39NC UNIT SIZE CHILLED WATER/ DIRECT EXPANSION Large Face Area Nominal Capacity (cfm) at 550 fpm 17,898 21,334 27,052 33,446 40,567 50,401 Size (Length x Width) (in.) x27 1 2(U) x 30 (U) x35(u) 113x37 1 2(U) x 40 (U) x 50 (U) x 30 (L) x32 1 2(L) x35(l) 113x40 (L) x42 1 2(L) x52 1 2(L) Total Face Area (sq ft) Medium Face Area Nominal Capacity (cfm) at 550 fpm 14,785 17,067 21,255 26,973 33,191 40,567 Size (Length x Width) (in.) x x x55 113x30 (U) 113x32 1 2(L) x32 1 2(U) x 35 (L) x 40 (U) x42 1 2(L) Total Face Area (sq ft) Bypass (Chilled Water Only) Nominal Capacity (cfm) at 550 fpm 14,785 17,067 21,255 26,973 31,962 40,567 Size (Length x Width) (in.) x22 1 2(U) x 25 (L) x25(u) x25(l) x27 1 2(U) x27 1 2(L) 113x30 (U) 113x32 1 2(L) x x x 40 (U) x42 1 2(L) Total Face Area (sq ft) HOT WATER HEATING Medium Face Area Nominal Capacity (cfm) at 700 fpm 18,818 21,722 27,052 34,329 42,243 51,630 Size (Length x Width) (in.) x x x55 113x30 (U) 113x32 1 2(L) x32 1 2(U) x 35 (L) x 40 (U) x42 1 2(L) Total Face Area (sq ft) Bypass Nominal Capacity (cfm) at 700 fpm 13,866 16,291 20,904 27,463 32,856 39,114 Size (Length x Width) (in.) x x x x x x 30 (U) x32 1 2(L) Total Face Area (sq ft) STEAM HEATING COIL Medium Face Area Nominal Capacity (cfm) at 700 fpm 17,640 20,650 26,530 31,010 39,130 50,260 Size (Length x Width) (in.) x x x54 112x27(U) 112x30(L) x30(u) x39(u) x33(l) x42(l) Total Face Area (sq ft) Bypass Nominal Capacity (cfm) at 700 fpm 12,950 15,470 20,650 26,110 31,640 35,420 Size (Length x Width) (in.) x x x42 112x x x27(u) x30(l) Total Face Area (sq ft) LEGEND U Upper Coil L Lower Coil 7

8 Table 3 Coil Volume (gal. water) 39NC UNIT SIZE CHILLED WATER Large Face Area 4-Row Row Row Row Medium Face Area 4-Row Row Row Row Bypass Face Area 4-Row Row Row Row HOT WATER Large Face Area 1-Row Row Medium Face Area 1-Row Row Bypass Face Area 1-Row Row NOTE: One gallon of water weighs 8.33 lbs. CIRCUIT TYPE FACE AREA Table 4 Chilled Water Coil Connection Sizes 39NC UNIT SIZE Nozzle Size (in. MPT) HALF LARGE, MEDIUM, FULL BYPASS LARGE DOUBLE MEDIUM BYPASS NOTE: The following sizes have two coils: Large and bypass face area sizes 32-92, medium face area sizes FACE AREA Table 5 Hot Water Coil Connection Sizes 39NC UNIT SIZE Nozzle Size (in. MPT) LARGE MEDIUM BYPASS NOTE: The following sizes have two coils: medium face area sizes 61-92, bypass face area size 92. 8

9 FACE AREA LARGE MEDIUM BYPASS Table 6 Steam Coil Connection Sizes 39NC UNIT SIZE CONNECTION Nozzle Size (in. MPT) Inlet Outlet Inlet Outlet Inlet Outlet NOTE: The following sizes have two coils: medium face area sizes 61-92; bypass face area size 92. Table 7 Operating Charge (Approximate) Direct Expansion Coil NUMBER OF ROWS FACE AREA 39NC UNIT SIZE Refrigerant R-22 (lb) Large Medium Large Medium Large Medium Table 8 Coil Moisture Blowoff Limits (Fpm) FINS ALUMINUM COPPER PER INCH FINS FINS NOTE: See ACAPS (applied coil and air handler performance and selection) computer program for specific limitations. Data shown is for general use in worst case conditions. Table 9 Airfoil Fan Physical Data 39NC UNIT SIZE Wheel Diameter (in.) Max Speed (rpm) Fan Sheave Bore (in.) Fan Shaft Wt (lb) Fan Wheel Wt (lb) No. of Fan Blades MOTOR FRAME SIZE Maximum ODP 215T 215T 254T 256T 256T 286T 286T 326T 364T 365T 404T 405T 405T TEFC 213T 213T 215T 256T 256T 284T 284T 324T 324T 364T 364T 404T 404T Minimum 143T 143T 145T 145T 182T 182T 182T 182T 182T 182T 184T 213T 213T MOTOR HP Maximum Minimum LEGEND ODP Open Drip Proof TEFC Totally-Enclosed, Fan Cooled NOTES: 1. Motor data applies to units with or without inlet guide vanes. 2. Data shown is for 60 Hz motors. Contact Application Engineering for 50 Hz applications. 9

10 Table 10 Forward-Curved Fan Physical Data 39NC UNIT SIZE* Wheel Diameter (in.) Max Speed (rpm) Fan Sheave Bore (in.) Fan Shaft Wt (lb) Fan Width (in.) Fan Wheel Wt (lb) No. of Fan Blades MOTOR FRAME SIZE Maximum ODP 213T 215T 254T 254T 256T 284T 284T 326T 364T 365T 365T TEFC 184T 213T 215T 254T 256T 284T 284T 324T 324T 364T 364T Minimum 143T 143T 145T 145T 182T 182T 182T 182T 182T 182T 184T MOTOR HP Maximum Minimum LEGEND ODP Open Drip Proof TEFC Totally-Enclosed, Fan Cooled *Forward-curved fans available on sizes only. NOTES: 1. Motor data applies to units with or without inlet guide vanes. 2. Data shown is for 60 Hz motors. Contact Application Engineering for 50 Hz applications. PREINSTALLATION Inspection Inspect the unit. If unit is damaged, file a claim with the shipping company. Check the packing list to ensure that the correct items have been received and notify your Carrier representative of any discrepancy. Rigging Units can be rigged into place on top of the building using a crane or helicopter. Check the unit weight to make sure the rigging equipment is capable of handling the load. Refer to shipping company s bill of lading for the measured shipping weight of the unit. For unit weight estimation, component, coil, and motor weights are listed in Tables Component dimensions are listed in Fig. 5 and 6. Add the airway lengths of all components in the unit to obtain the overall unit length. To maintain watertight integrity, do not disassemble the unit before rigging. See Installation, Rigging section, for further rigging information. Long-Term Storage If long term storage is required, observe the following precautions: The storage site should be level, rigid, and clean of construction debris. If the site is in a heavy rain area, set the unit off the ground. Do not store the unit in heavy construction traffic area. Ensure that all coil connections have shipping caps in place. Cover the unit with a waterproof tarpaulin or plastic material. If the unit is stored on the ground, place plastic ground cover under the unit. Secure the cover with tie-downs if the unit is stored outdoors. Do not remove the cover or coil connection caps until the unit is installed. Do not stack units or store equipment on top of unit. Monthly: Using the doors for entry into the fan section, slowly rotate the fan and motor manually for a number of turns. This will redistribute the bearing grease and help prevent bearing corrosion. Service Clearance When planning the placement of the unit, ensure adequate space for service access. Typical service operations can require removing the coils and filters and accessing the motor and damper linkages. See Fig. 7 for required service clearances. Also ensure clearances conform to local codes. 10

11 Table 11 Nominal Component Weights (lb) DRAW-THRU COMPONENTS COMPONENT 39NC UNIT SIZE ACC AFS AMX ANG BCC BCF BPH BPH CDC CIC CIC CIC EMB FBP FCS FLT FMB HRS LCS LCS LCS MCS MCS MCS MHS MXB4, PLN PLN RAF1, RFC1, SHS BLOW-THRU COMPONENTS COMPONENT 39NC UNIT SIZE ACC AFS BCF BCS CDC DIF DPL FCS PLN NOTES: 1. Coil section weights are without coil. See Table 13 for dry coil weights. 2. Fan section weights are without motors or drives. See Table 12 for motor weights. Multiply motor weight by 0.10 to estimate drive weight. 3. Filter section weights are without filters. Filters are not shipped with the unit. 4. For complete component definition, see Table 1. 11

12 MOTOR TYPE Table 12 Motor Weights (Lb) OPEN DRIP-PROOF (ODP) MOTOR HP Standard High Efficiency MOTOR TYPE TOTALLY ENCLOSED FAN COOLED (TEFC) MOTOR HP Standard High Efficiency NOTES: 1. Weight of sheaves and belts not included. 2. Motor weights vary by vendor. 3. Multiply motor weight by 0.10 to estimate drive weight. 12

13 COIL TYPE CHILLED WATER OR DIRECT EXPANSION HOT WATER STEAM FACE AREA LARGE MEDIUM BYPASS* LARGE MEDIUM BYPASS LARGE MEDIUM BYPASS ROWS * * Table 13 Dry Coil Weights (Lb) FINS 39NC UNIT SIZE PER IN *Chilled water only. NOTES: 1. Weights shown include headers and are the sum of two coils where applicable. 2. Coils are full-length. 3. Weights shown are for aluminum-fin coils; for copper fins, multiply by To obtain approximate wet (filled) weight, multiply by

14 SIZE HORIZONTAL DRAW-THRU WITH OR WITHOUT BYPASS BLOW-THRU COMPONENTS DIMENSIONS (ft-in.) 39NC UNIT SIZE W H* *Height to high side of sloped top. Slope is 1 4 in. per foot minimum. Low-side height is in. less on sizes and 3 in. less on 26 size unit. Height includes in. vertical flange on roof panels. Fig. 5 Dimensions, Unit Sizes

15 HORIZONTAL DRAW-THRU COMPONENT AIRWAY LENGTHS (ft-in.) COMPONENT CIC CIC CIC3* RAF1, RFC1, EMB MXB4, FMB ANG BCF FLT AMX ACC PLN PLN HRS MHS SHS LCS LCS2, MCS MCS2, FBP BCC BPH BPH AFS FCS CDC BLOW-THRU COMPONENT AIRWAY LENGTHS (ft-in.) COMPONENT AFS FCS ACC PLN DIF BCF BCS DPL CDC *See Service Area Requirements, Fig. 7 for intake hood length. Length shown is for base of component. NOTE: See Table 1 for component description. Fig. 5 Dimensions, Unit Sizes (cont) 15

16 SIZE HORIZONTAL DRAW-THRU WITH OR WITHOUT BYPASS BLOW-THRU COMPONENTS DIMENSIONS (ft-in.) 39NC UNIT SIZE W H** *Unit sizes 61 and larger have 2 coils. Unit size 92 has 2 coils. **Height to high side of sloped top. Slope is 1 4 in. per foot minimum. Low-side height is 3 in. less on size units. Height includes in. vertical flange on roof panels. Fig. 6 Dimensions, Unit Sizes

17 HORIZONTAL DRAW-THRU COMPONENT AIRWAY LENGTHS (ft-in.) COMPONENT CIC CIC CIC3* RAF1, RFC1, EMB MXB4, FMB ANG BCF FLT AMX ACC PLN PLN HRS MHS SHS LCS MCS MCS MCS FBP BCC BPH BPH AFS FCS CDC BLOW-THRU COMPONENT AIRWAY LENGTHS (ft-in.) COMPONENT AFS FCS ACC PLN DIF BCF BCS DPL CDC *See Service Area Requirements, Fig. 7 for intake hood length. Length shown is for component base. NOTE: See Table 1 for component description. Fig. 6 Dimensions, Unit Sizes (cont) 17

18 HOOD CLEARANCE (EMB1 EXHAUST MIXING BOX) E (SHOWN SEPARATELY FOR CLARITY) HOOD CLEARANCE (CIC3 INLET) D BASE UNIT (ALL AREAS OF UNIT EXCEPT COILS AND FANS) 2'-2" [660] COIL FAN L* W 2'-0" ** [610] L* L* B A DIMENSIONS (ft-in.) 39NC UNIT SIZE A B D (CIC3) E (EMB1) *Airway length. See Fig. 5 and 6 for length of this area. Unit width. See Fig. 5 and 6 for width of this area. **Service area required for access door on side of fan opposite motor. Fig. 7 Service Area Requirements 18

19 Internal Vibration Isolation Units have internal vibration isolation and must be prepared as described in this section before they are installed. When adjusting fan isolation components, DO NOT enter or reach into the fan cabinet while fan is running. Serious injury can result. Be sure to disconnect power and tag controls before making adjustments. REMOVING HOLDDOWN BRACKET SCREWS Remove the holddown bracket screws (Fig. 8) as follows: 1. Open the fan access door. The yellow holddown brackets are on both sides of the fan. 2. Remove screws from top of each holding bracket so fan sled floats freely on isolator springs. 3. Discard screws. Holding bracket can remain attached to bottom of fan sled. 4. Remove and discard wood shipping blocks inserted between fan and side walls, if supplied. 5. Adjust isolators if required and close fan access door. NOTE: Drives, isolators, and sheaves are prealigned at factory and should not require adjustment. See following section. ADJUSTING ISOLATOR SPRINGS Units with factorysupplied motors and drives are preset to ± 1 8-in. clearance between the base frame assembly and the bottom panels; field adjustment of the isolator springs is not normally required. Units that receive field-supplied motors require isolator spring adjustment to in. nominal clearance after the fan motor, sheaves, and belts have been installed. When field-supplied motors and drives have been installed, adjust the isolator springs as shown in Fig. 8 and described as follows: 1. Loosen the locknut. 2. Turn the adjusting stem until the specified clearance of ± 1 8-in. is obtained. (Turn clockwise to decrease clearance or counterclockwise to increase clearance.) 3. Tighten the locknut. 4. Repeat for each of the isolator springs and ensure that the fan sled is floating on the springs. Roof Curb Roof curbs must be field-supplied for 39NC units and should be installed according to the manufacturer s instructions. Before installing roof curb, check overall unit length as described in the Preinstallation section. Figure 9 shows recommended curb dimensions and typical construction. IMPORTANT: Verify installed curb dimensions before attempting to rig the unit and install it on the curb. After curb is installed, fabricate inlet and discharge according to the unit configuration. Dimensions for inlet and discharge locations are shown in Fig. 10. Before the unit is installed, gasketing must be installed between the curb and unit as shown in Fig. 11. This gasket material is often supplied by the curb manufacturer. If gasket is not supplied with the curb, recommended fieldsupplied gasket material is 1 2-in. thick by 2-in. wide closedcell neoprene. When curb is installed, place gasket on curb without stretching or overlapping the material, which can cause gaps or leaks. Butt all joints evenly and avoid creating gaps where water can leak into the curb. Make sure seams in gasket material overlap seams in the curb rail. See Fig. 11 for installation details. After gasket is in place, rig unit into position with overhead crane or helicopter as described in Installation, Rigging section. Locate unit on curb so it is correctly oriented with respect to curb inlet and discharge locations. Pier or Beam Mount As an alternative to curb mounting, units can also be mounted on I-beams or piers. For units mounted on I-beams, the beams must run the continuous length of the unit. If seismic criteria apply, cross-pieces must be added between the beams according to seismic calculations. See Fig. 12 for a typical installation. For pier-mounted units, one pier must be installed in each corner of the unit at the junction of the baserail corners. A minimum of 4 piers can be used for size units up to 15 ft long and size units up to 10 ft long. For each additional 15 ft of length for size units or 10 ft of length for size units, install one additional pier on each side of the unit underneath the baserails. See Fig. 12 for a typical installation. FAN REMOVE TOP SCREWS ONLY HOLDDOWN BRACKET (2 SIDES) Fig. 8 Removing Holddown Bracket Screws and Adjusting Isolator Spring 19

20 UNIT MOUNTING DETAIL 5 7/16 in. 1 7/8 in. TYPICAL UNIT BOTTOM 3 in. 2 7/8 in. 7/8 in. 5 in. CURB 2 3/4 in. 1 7/8 in. TYPICAL CURB DIMENSIONS (BASED ON 1 7/8 in. CURB RAIL WIDTH)* A AIRFLOW B *Adjust A and B dimensions accordingly if rail width is different from inches. CURB DIMENSIONS (ft-in.) 39NC UNIT SIZE A (Width) B (Airway Length) Varies By Unit Component NOTES: 1. The A dimension equals unit width minus inches. 2. The B dimension equals the unit airway length (sum of all components, including CIC and CDC) minus inches. 3. See Table 1 for component description and Fig. 5 and 6 for component airway lengths. Fig. 9 Determining Roof Curb Dimensions 20

21 MIXING BOX (MXB4, FMB4) MXB4 AND FMB4 INLET DIMENSIONS (ft-in.) 39NC UNIT SIZE A B C D RETURN FAN (RAF1, RFC1) DISCHARGE PLENUM (DPL1) RAF1 AND RFC1 INLET DIMENSIONS (ft-in.) 39NC UNIT SIZE A B C D * * *RAF1 only. DPL1 DISCHARGE DIMENSIONS (ft-in.) 39NC UNIT SIZE E F G H Fig. 10 Curb Inlet and Discharge Locations 21

22 GASKET SEAM BUTT JOINTS, DO NOT OVERLAP WRONG METHOD INSTALLATION This section describes how to install 39NC units. The base unit is shipped fully assembled (except for intake hoods on larger units) on a single skid up to 40 ft in length. To maintain watertight integrity, DO NOT attempt to disassemble the unit to install it. Rigging Units are shipped fully assembled and are designed to be lifted into final location by crane or helicopter using the lifting lugs on the base of the unit. Rigging details are shown in Fig. 13. Spreader bars must be used when rigging unit to avoid crushing or damaging unit top edges. Damage can result in air or water leaks. On curb installations, lower unit directly into place, ensuring that roof curb gasket does not shift or curl. When unit is in its final location, do not remove the caps from the coil connections until the coil is ready for piping. RAIL SEAM GASKET SEAM RIGHT METHOD RAIL SEAM Fig. 11 Installation of Curb Gasket BEAM MOUNT PIER MOUNT* L *Minimum number of piers shown for pier mounted unit. See tables below for number of equally-spaced piers required. QUANTITY OF PIERS REQUIRED 39NC UNIT LENGTH L, FT UNIT SIZE Fig. 12 Pier or Beam Mounting 22 39NC UNIT LENGTH L, FT UNIT SIZE

23 VERTICAL LIFT SPREADER BARS 15 MAXIMUM ASSEMBLED UNIT UNIT LENGTH NOTES: 1. Rig unit using all lifting lugs on the unit s base frame. 2. Use spreader bars to prevent damaging top panels and to ensure a vertical lift at all lifting points. Lifting angles greater than 15 from vertical will damage the unit. 3. Lift unit by crane or helicopter. Ensure rigging device can lift unit weight safely. 4. Ensure gasket on roof curb does not shift or curl when placing unit. Fig. 13 Rigging Sheet Metal Duct Connections For vertical supply and return units, tools or parts could drop into ductwork and cause an injury. Install 90 degree turns in the supply and return ductwork between the unit and the conditioned space. If a 90 degree elbow cannot be installed, then grilles of sufficient strength and density should be installed to prevent objects from falling into the conditioned space. Attach the return and/or supply ductwork to the air inlet and outlet connection collars (provided at the bottom or ends of the unit) using sheet metal screws. No provisions have been made for attaching the ductwork to the curb. The ductwork must be sealed against the unit with caulk or other suitable material to avoid air or water leaks. See Fig. 14. The return and supply ducts must be supported independently from the unit. Do not exert weight or downward force on the unit other than minimal force required for duct attachment. IMPORTANT: When the air handler arrangement includes a return fan, MXB7 mixing box, filter mixing box, or discharge plenum, and the return and/or supply ducts are confined within the curb, then extra caution is necessary when attaching the ductwork. After the unit is installed, it is difficult to repair air or water leaks at these connections. Inlet and discharge locations and dimensions for withinthe-curb connections are shown in Fig. 10. Duct connections for CIC2 inlet and CDC2 outlet with connections outside the curb are shown in Fig. 15 and 16. UNIT BOTTOM PANEL GASKET OR CAULK FIELD SUPPLIED DUCTWORK Fig. 14 Connecting Duct to Unit (MXB4, FMB4, or DPL1) 23

24 CIC2 INLET DIMENSIONS END VIEW 10 1/4" F 7 7/8" E G DIMENSIONS (ft-in.) 39NC UNIT SIZE E F G [387] [533] [900] [1000] [1200] [1400] [1500] 5-3 [1600] [1800] [1900] [679] [2100] [2400] [825] [2700] [971] [3100] [1263] [271] [375] [371] [469] [565] [622] [725] [569] [672] [724] [933] [885] [984] Fig. 15 CIC2 Duct Connections 24

25 CDC2 DISCHARGE DIMENSIONS END VIEW F E H G RIGHT-HAND UNIT DIMENSIONS (ft-in.) CDC2 USED WITH 39NC UNIT SIZE Forward-Curved (FCS Fans) Airfoil (AFS Fans) E F G H E F G H Fig. 16 CDC2 Duct Connections 25

26 Doors All unit access doors are designed for outside use. Each door has 2 seals: The outer seal is a water seal and the inner seal is an air seal. It may appear that a portion of the outer seal at the bottom of the door is missing, but this gap provides an atmospheric break between the inner and outer seal. The gap is required to relieve positive or negative pressure from building between the door seals. Intake Rain Hoods Two types of rain hoods are supplied on 39NC units. One type is used on the CIC3 intake section, and a second type is supplied for the EMB1 (exhaust mixing box). The 2 types of hoods are similar except for height and the slope of the hood angle. See Fig. 17 for a typical hood. Both types of intake rain hoods keep rain and snow out of the air intake; both also have integral demisters. The demisters remove atomized water from the air before it enters the unit and also prevent the entry of birds and debris. The demisters are factory supplied and installed in the hoods on the CIC3 and EMB1 sections. For smaller units that have a CIC3 intake section, the rain hood is factory assembled to the unit. Larger units that use the CIC3 section and all units that have EMB1 sections have the rain hoods shipped detached from the unit for field installation, due to shipping restrictions. On these units, use the supplied gasket material and fasteners to attach the intake rain hood to the intake section once the unit is in its final location. Wiring Install all wiring in accordance with National Electrical Code (NEC) and applicable local codes. To maintain watertight integrity, avoid drilling holes in (or attaching hardware to) unit outer panels. DO NOT drill holes in bottom panels for wiring or tubing; holes in the panels can be paths for water leakage into the building. Use wiring access conduits in bottom panels of fan sections for control and power wiring. Access conduit sizes are in. ID for unit sizes and in. ID for unit sizes After power and control lines have been routed through the conduit to connection points, seal the wires in the conduit with a non-conductive sealant to prevent air infiltration. Use a non-conductive, non-hardening sealant. Permagum (manufactured by Schnee Morehead) or sealing compound, thumb grade (manufactured by Calgon), are acceptable materials. For detailed standpipe location dimensions, see Fig. 18 or consult certified drawings. INTAKE HOOD DEMISTERS (4 ROWS SHOWN) GASKET Select motor branch circuit wire sizing according to the amp values shown in Table 14. Size overload protection or fuses according to the recommendation on the motor nameplate. Locate unit disconnect in accordance with NEC or local codes. Table 14 Motor Full-Load Current Values for Sizing Electrical Branch Circuits INDUCTION TYPE MOTOR SQUIRREL-CAGE AND HP WOUND-ROTOR AMPERES 200V 208V 230V 460V 575V NOTE: Branch circuit wire sizing can be selected using this table. Overload protection or fuse sizing must be selected according to information on motor nameplate. Fan Motors and Drives Field-supplied motors should be listed or approved by UL (Underwriter s Laboratories) or ETL (Engineering Testing Laboratories) and CSA (Canadian Standards Association) or ETL, Canada. When installing motors in the field, locate the electrical junction box toward the center of the unit. This arrangement is required for correct belt tension. Use the smallest mounting holes in the mounting base that will accommodate the motor and provide minimum overhang (see Fig. 19). Tighten the motor holddown bolts. JUNCTION BOX CONDENSATE PREVENTION When air handlers are installed outdoors, precautions must be taken to prevent condensation from forming inside the junction box of the internally mounted motor. Standard installation practice is to mount the motor starter or fused disconnect box adjacent to the air handler and enclose the power wiring to the motor in flexible conduit. The sheet metal housing of the disconnect switch or motor starter is not airtight (even when a box meeting NEMA [National Electrical Manufacturers Association] IV standards is used). Thus, warm moist air can migrate through the flexible conduit to the junction box on the motor. With the motor located inside the unit, the motor temperature is that of the cool supply air; thus, condensate can form inside the junction box and, possibly, on the live terminal lugs. To prevent the moist air from migrating through the conduit to the motor, seal the power wires inside the flexible conduit at the motor starter or fused disconnect (Fig. 20). Use a non-conductive, non-hardening sealant. Permagum (manufactured by Schnee Morehead) or sealing compound, thumb grade (manufactured by Calgon), are acceptable materials. Fig. 17 Intake Hood 26