Product Data WEATHEREXPERT™ 48/50N2,N3,N4,N5,N6,N7,N8,N9 Packaged Rooftop Cooling Units with Gas Heat, Optional Electric Heat, or Hydronic Heat and ComfortLink Controls 75 to 150 Nominal Tons WeatherExpert ™ Carrier’s 48/50N Series commercial packaged rooftops offer: • Puron® refrigerant (R-410A) • multiple efficiency and capacity choices • electronic expansion valves • double wall foam panel construction • mixed air and final filter options • flexible blank section and plenum options • non-overloading
Features/Benefits (cont) Design flexibility The 48/50N Series rooftop units with ComfortLink controls are designed to meet all customer requirements for new construction, replacement jobs, or special applications.
Novation® heat exchanger technology cycling, and improve comfort in the space. The Novation heat exchanger design with microchannel condenser coil is a robust, cost effective alternative to traditional coil design for standard applications. Microchannel coils are also sturdier than other coil types, making them easier to clean without causing damage to the coil. Due to the compact all aluminum design, microchannel coils reduce overall unit operating weight.
Features/Benefits (cont) Fan modulation The ComfortLink controller maintains supply duct pressure on VAV models by monitoring the factory-installed duct pressure transducer and sending commands to the supply fan variable frequency drive (VFD). The VFD varies the supply fan airflow to maintain the user-established duct pressure set point in the supply duct.
• VAV units provide multiple stage, cooling capacity control for improved part load operation and greater efficiency • optional digital compressors provide a nearly infinite number of steps of capacity for unmatched load matching and part load performance • Humidi-MiZer adaptive dehumidification system • refrigeration system designed to operate with outdoor temperatures down to 32 F, optionally to –20 F.
Features/Benefits (cont) Electric heat units (50N units) The 50N units may be equipped with factory-installed electric heat, with 3 heat sizes available for every unit. The heaters are resistance type, open wire nichrome elements, insulated with ceramic bushings, and include operating and safety controls. The standard heater control is a 2-stage type. An optional SCR control is available for applications requiring precise leaving air temperature control.
Condenser Section • Novation® MCHX technology • High-efficiency option • Replaceable core filter drier option • R-410A refrigerant Heating Systems • Gas, electric, or hydronic • Staged or modulating control • Induced-draft gas heat design Supply/Return Configurations • Vertical • Horizontal • Mixed a48-8674 Scroll compressors • Efficient, dependable • Up to 8 steps of capacity control • Variable capacity option 7
Model number nomenclature a48-8671 48N UNITS 48 N2 D N 6 0 Option Code 48 – Cooling Unit with Gas Heat Configuration N2 – Vertical Suppy/Return, CV/SAV ComfortLink Controls N3 – Vertical Supply/Return, VAV ComfortLink Controls N4 – Horizontal Suppy/Return, CV/SAV ComfortLink Controls N5 – Horizontal Suppy/Return, VAV ComfortLink Controls N6 – Vertical Suppy/Horizontal Return, CV/SAV ComfortLink Controls N7 – Vertical Supply/Horizontal Return, VAV ComfortLink Controls N8 – Horizontal Suppy/Vertical Return,
50N UNITS a50-8781 50 N2 D N 6 0 Option Code Factory Options See note below 50 – Cooling Only Unit Configuration N2 – Vertical Suppy/Return, CV/SAV ComfortLink Controls N3 – Vertical Supply/Return, VAV ComfortLink Controls N4 – Horizontal Suppy/Return, CV/SAV ComfortLink Controls N5 – Horizontal Suppy/Return, VAV ComfortLink Controls N6 – Vertical Suppy/Horizontal Return, CV/SAV ComfortLink Controls N7 – Vertical Supply/Horizontal Return, VAV ComfortLink Controls N8 – Horizontal Suppy/Vertical Return, C
Ratings and capacities UNIT DESIGN AIRFLOW LIMITS UNIT SIZE (NOMINAL CAPACITY, TONS) N (75) P (90) Q (105) R (120) S (130) T (150) UNIT TYPE 48N Low Heat 48N High Heat 50N Electric Heat 50N No Heat 48N Low Heat 48N Medium Heat 48N High Heat 50N Electric Heat 50N No Heat 48N Low Heat 48N Medium Heat 48N High Heat 50N Electric Heat 50N No Heat 48N Low Heat 48N Medium Heat 48N High Heat 50N Electric Heat 50N No Heat 48N Low Heat 48N Medium Heat 48N High Heat 50N Electric Heat 50N No Heat 48N Low Heat 48N
TWO-STAGE GAS HEATING CAPACITIES - 48N UNITS (Natural Gas on All Units) UNIT SIZE (NOMINAL CAPACITY, TONS) NOMINAL CAPACITY N (75) 75 Low Heat 75 High Heat 90 Low Heat 90 Medium Heat 90 High Heat 105 Low Heat 105 Medium Heat 105 High Heat 120 Low Heat 120 Medium Heat 120 High Heat 130 Low Heat 130 Medium Heat 130 High Heat 150 Low Heat 150 Medium Heat 150 High Heat P (90) Q (105) R (120) S (130) T (150) GAS INPUT (1000 Btuh) Stage 1 Stage 2 600 800 900 1200 600 800 900 1200 1200 1600 600 800 900 1200 1
Ratings and capacities (cont) MODULATING GAS HEATING CAPACITIES — 48N UNITS (Natural Gas on All Units) UNIT SIZE (NOMINAL CAPACITY, TONS) NOMINAL CAPACITY N (75) 75 Low Heat 75 High Heat 90 Low Heat 90 Medium Heat 90 High Heat 105 Low Heat 105 Medium Heat 105 High Heat 120 Low Heat 120 Medium Heat 120 High Heat 130 Low Heat 130 Medium Heat 130 High Heat 150 Low Heat 150 Medium Heat 150 High Heat P (90) Q (105) R (120) S (130) T (150) GAS INPUT (1000 Btuh) Stage 1 Stage 2 108 800 108 1200 108 800 108 12
Physical data 48/50N SIZES N-T (75-150 TONS NOMINAL CAPACITY) BASE UNIT NOMINAL CAPACITY (tons) WEIGHT (lb) Base Unit* Split Unit - Main Section Split Unit - Return Section COMPRESSORS Quantity Oil Charge (oz) per Compressor Compressor A1 Compressor A2 Compressor A3 Compressor A4 Compressor B1 Compressor B2 Compressor B3 Compressor B4 Stages of Capacity, % Total Capacity Number of Refrigerant Circuits REFRIGERANT Type Charge Amount METERING DEVICE Type...
Physical data (cont) 48/50N SIZES N-T (75-150 TONS NOMINAL CAPACITY) (cont) BASE UNIT NOMINAL CAPACITY (tons) HUMIDI-MIZER® COIL Type Material Quantity Surface Total Face Area (sq ft) STANDARD AND HIGH CAPACITY HOT WATER COILS Type Material Quantity Tube Type Rows (each) FPI Total Face Area (sq ft) STANDARD AND HIGH CAPACITY STEAM COIL Type Material Quantity Tube Type Connection Size, Length (in.
48/50N SIZES N-T (75-150 TONS NOMINAL CAPACITY) (cont) BASE UNIT NOMINAL CAPACITY (tons) OPTIONAL POWER EXHAUST Power Exhaust Diameter (in.) Wheel and Blade Type Maximum Allowable Cfm Maximum Allowable Speed (rpm) Shaft Diameter at Pulley (in.) High Static Power Exhaust Diameter (in.) Wheel and Blade Type Maximum Allowable Cfm Maximum Allowable Speed (rpm) Shaft Diameter at Pulley (in.) OPTIONAL RETURN FAN Return Fan Diameter (in.
Physical data (cont) MULTIPLE UNIT MINIMUM SEPARATION D A E F B MINIMUM SPACING (ft) C UNIT 48 Series 50 Series A B C D E F 12 8 12 10 10 10 10 8 8 10 10 10 a48-8682 16
REFRIGERANT CHARGE UNIT SIZE (NOMINAL CAPACITY, TONS) N (75) P (90) Q (105) R (120) S (130) T (150) UNIT CONFIGURATION Standard Capacity Standard Efficiency High Capacity Standard Efficiency Standard Capacity High Efficiency High Capacity High Efficiency Standard Capacity Standard Efficiency High Capacity Standard Efficiency Standard Capacity High Efficiency High Capacity High Efficiency Standard Capacity Standard Efficiency High Capacity Standard Efficiency Standard Capacity High Efficiency High Capa
Physical data (cont) FAN AND DRIVE INFORMATION FAN MOTOR RPM MOTOR SHAFT SIZE (in.) FAN RPM 50 1770 2.125 1800 4B5V70 B 2 1/8 4B5V68 B 2 1/4 5VX530 4 1821/1821 40 1770 2.125 1600 3B5V68 B 2 1/8 3B5V74 B 2 1/4 5VX540 3 1628/1628 30 1765 1.875 1450 3B5V70 B 1 7/8 3B5V86 B 2 1/4 BX55 3 1448/1448 25 1765 1.875 1400 3B5V64 B 1 7/8 3B5V80 B 2 1/4 BX53 3 1425/1425 20 1765 1.625 1250 3B5V56 B 1 5/8 3B5V80 B 2 1/4 BX53 3 1255/1255 15 1770 1.
FAN AND DRIVE INFORMATION (cont) MOTOR MOTOR HP RPM FAN MOTOR SHAFT SIZE (in.) FAN RPM FAN SHAFT SIZE (in.) DRIVE SHEAVE BROWNING BUSHING TYPE DRIVEN BUSHING SHEAVE TYPE BROWNING BELTS QTY OF BELTS FAN SPEED (rpm) RETURN FAN Standard Return Fan All Sizes High Static Return Fan 75 Tons Nominal Capacity High Static Return Fan 90 Tons Nominal Capacity High Static Return Fan 105-150 Tons Nominal Capacity 50 1770 2.
Physical data (cont) STAGING SEQUENCES SIZE N STAGING SEQUENCE WITH MLV (75 TON NOMINAL CAPACITY) STAGE COMP A1 A2 B1 B2 B3 UNIT 075 0 1* 1 OFF OFF OFF OFF OFF ON OFF OFF OFF OFF ON OFF OFF OFF OFF 0% 18% 23% SEQUENCE 2 Compressor Status ON OFF ON OFF OFF Total Capacity 41% 3 4 5 ON ON ON OFF OFF ON ON ON ON OFF ON ON ON ON ON 65% 82% 100% *Minimum load valve (MLV). MLV is enabled on Circuit A when decreasing from stage 1 to stage 0 to provide an increased stage of capacity.
STAGING SEQUENCES (cont) SIZE P, Q STAGING SEQUENCE WITH DIGITAL COMPRESSOR (90 AND 105 TON NOMINAL CAPACITY) STAGE COMP A1 A2 A3 B1 B2 B3 UNIT 090 105 0 1 2 OFF OFF OFF OFF OFF OFF ON OFF OFF OFF OFF OFF ON OFF OFF ON OFF OFF 0% 0% 8% to 15% 8% to 17% 26% to 33% 25% to 33% SEQUENCE 3 Compressor Status ON ON OFF ON OFF OFF Total Capacity 41% to 49% 42% to 50% 4 5 6 ON ON OFF ON ON OFF ON ON ON ON ON OFF ON ON ON ON ON ON 59% to 67% 58% to 67% 74% to 82% 75% to 83% 92% to 100% 92% to 100%
Physical data (cont) OPERATING WEIGHTS OF OPTIONS AND ACCESSORIES (lb) OPTION OR ACCESSORY Economizer Filters 2 in. MERV 7 4 in. MERV 8 4 in. MERV 14 12 in. MERV 14 Bag with 2 in. Pre-Filter 12 in. MERV 14 Bag with 4 in. Pre-Filter 19 in. MERV 15 Bag with 2 in. Pre-Filter 19 in. MERV 15 Bag with 4 in. Pre-Filter 12 in. MERV 14 Cartridge with 2 in. Pre-Filter 12 in. MERV 14 Cartridge with 4 in.
OPERATING WEIGHTS OF OPTIONS AND ACCESSORIES (lb) (cont) OPTION OR ACCESSORY Supply/PE/Return Motor Includes VFD 460 Volt TEFC 7.5 Hp 10 Hp 15 Hp 20 Hp 25 Hp 30 Hp 40 Hp 50 Hp 60 Hp 75 Hp 100 Hp Supply/PE/Return Motor Includes VFD 575 Volt ODP 7.5 Hp 10 Hp 15 Hp 20 Hp 25 Hp 30 Hp 40 Hp 50 Hp 60 Hp 75 Hp 100 Hp Supply/PE/Return Motor Includes VFD 575 Volt TEFC 7.5 Hp 10 Hp 15 Hp 20 Hp 25 Hp 30 Hp 40 Hp 50 Hp 60 Hp 75 Hp 100 Hp Supply/PE/Return Motor Includes VFD Bypass 7.
Options and accessories ITEM GAS HEAT (48N units only) Low, Medium or High Gas Heat — Aluminized Heat Exchanger Low, Medium or High Gas Heat — Stainless Steel Heat Exchanger Ultra High Gas Heat — Stainless Steel Heat Exchanger Staged or Modulating Gas Heat — Stainless Steel Heat Exchanger Flue Extension ELECTRIC HEAT (50N units only) Low, Medium or High Electric Heat Staged or SCR Controlled Electric Heat HYDRONIC HEAT (50N units only) Low or High Capacity Hot Water Coil Low or High Capacity Steam Coil FILT
ITEM CONTROLS Outdoor Air cfm Measuring Station Supply Air cfm Measuring Station Exhaust Air cfm Measuring Station Controls Expansion Module (CEM) BACnet Communication Dual Point Power Connection System Pilot™ Interface Touch Pilot™ Interface Navigator™ Display Return Air CO2 Sensor CO2 Space Sensor Return Air Smoke Detector Return and Supply Air Smoke Detectors Installed Field Use Control Box Filter Switch Fan Status Switch (requires CEM) T-55 Space Temperature Sensor with Override T-56 Space Temperature S
Options and accessories (cont) Chassis arrangements (48 Series units) Standard chassis — The standard chassis may be provided with a bottom or side return air opening. The return air follows a straight-through path to the supply fan, then into the heating section and exits through a bottom or left side supply air outlet. The supply/return configuration may be mixed, e.g., bottom return with side supply. If the application utilizes an accessory roof curb, vertical ductwork is connected to the curb.
with optional modulating power exhaust or return fan in conjunction with an optional economizer. Factory-installed optional electric heat is available on these units. STANDARD CHASSIS VERTICAL SUPPLY/VERTICAL RETURN the ductwork is connected to flanges on the unit. Factoryinstalled optional electric heat is available on these units.
48N UNIT SIZES N, P, Q (75-105 TON NOMINAL CAPACITY) Base unit dimensions A48-8684 28
48N UNIT SIZES N, P, Q (75-105 TON NOMINAL CAPACITY) NOMINAL FIELD USE EXTENDED SUPPLY BLANK 2-PIECE CAPACITY/ FILTER COND A B C D E F G H J K CHASSIS FAN SECTION UNIT EFFICIENCY SECTION NO NO 2 498.11 314.42 48 177.02 266.07 499.35 202.75 119.76 — 313.36 NO 4 FT YES 2 564.61 380.92 48 195.27 284.32 565.85 221.00 119.76 — 379.86 8 FT YES 2 612.86 429.17 48 195.27 284.32 614.10 221.00 119.76 — 428.11 STD NO YES 2 576.86 393.17 48 255.77 344.82 578.10 281.50 119.76 — 392.11 YES 4 FT YES 2 625.11 441.
48N UNIT SIZES R, S, T (120-150 TON NOMINAL CAPACITY) Base unit dimensions (cont) A48-8685 30
48N UNIT SIZES R, S, T (120-150 TON NOMINAL CAPACITY) NOMINAL EXTENDED CAPACITY/ CHASSIS EFFICIENCY HIGH GAS HEAT* NO NO YES 120 STD EFF NO YES YES NO NO YES 120 HI EFF 130 ALL 150 STD EFF NO YES YES FIELD 2USE BLANK L PIECE COND A B C D E F G H J K FILTER SECTION HI UNIT SECTION NO NO 2 523.04 339.35 48 186.86 291.00 524.28 227.68 119.76 — 338.29 2 NO 4 FT YES 2 589.54 405.85 48 205.11 309.25 590.78 245.93 119.76 — 404.79 2 8 FT YES 2 637.79 454.10 48 205.11 309.25 639.03 245.93 119.
50N UNITS SIZES N, P, Q (75-105 TON NOMINAL CAPACITY) Base unit dimensions (cont) A50-8823 32
50N UNIT SIZES N, P, Q (75-105 TON NOMINAL CAPACITY) NOMINAL FIELD USE EXTENDED SUPPLY BLANK 2-PIECE CAPACITY/ FILTER COND CHASSIS FAN SECTION UNIT EFFICIENCY SECTION NO NO 2 NO 4 FT YES 2 8 FT YES 2 STD NO NO 2 YES 4 FT YES 2 8 FT YES 2 NO NO NO 2 NO 4 FT YES 2 8 FT YES 2 HIGH NO NO 2 YES 4 FT YES 2 75 ALL 8 FT YES 2 90 STD EFF NO NO 2 105 STF EFF NO 4 FT YES 2 8 FT YES 2 STD NO NO 2 YES 4 FT YES 2 8 FT YES 2 YES NO NO 2 2 NO 4 FT YES 8 FT YES 2 HIGH NO NO 2 YES 4 FT YES 2 8 FT YES 2 NO NO 3 NO 4 FT YES 3
50N UNITS SIZES R, S, T (120-150 TON NOMINAL CAPACITY) Base unit dimensions (cont) a50-8824 34
50N UNIT SIZES R, S, T (120-150 TON NOMINAL CAPACITY) NOMINAL EXTENDED CAPACITY/ CHASSIS EFFICIENCY FIELD USE FILTER SECTION NO NO YES 120 STD EFF NO YES YES NO NO YES 120 HI EFF 130 ALL 150 STD EFF NO YES YES BLANK SECTION 2-PIECE UNIT COND A B D F G H J K NO 4 FT 8 FT NO 4 FT 8 FT NO 4 FT 8 FT NO 4 FT 8 FT NO 4 FT 8 FT NO 4 FT 8 FT NO 4 FT 8 FT NO 4 FT 8 FT NO YES YES NO YES YES NO YES YES NO YES YES NO YES YES NO YES YES NO YES YES NO YES YES 2 2 2 2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 3 3 3
O'-13/16" [21] 0'-3" [76.2] 10'-8 7/8" [3274] 0'-1" [25.4] (CORNER CONNECTIONS AND SPLICE PLATE CONNECTIONS) RETURN BASE RAIL CROSS SECTION TYP ALL BASE RAILS 0'-1 3/4" [44] 4. CROSS SUPPORTS EQUALLY SPACED APPROX 5'-6' APART 3. DIMENSIONS IN [ ] ARE MILLIMETERS. 2. ROOF CURB: 14 GA.[VA03-56] STL. 1. ROOF CURB ACCESSORY IS SHIPPED DISASSEMBLED.
48N ROOF CURB SIZES N, P, Q (75-105 TON NOMINAL CAPACITY) PART NUMBER* CRRFCURB225A00 CRRFCURB226A00 CRRFCURB227A00 CRRFCURB228A00 CRRFCURB229A00 CRRFCURB230A00 CRRFCURB231A00 CRRFCURB232A00 CRRFCURB233A00 CRRFCURB234A00 CRRFCURB235A00 CRRFCURB236A00 CRRFCURB237A00 CRRFCURB238A00 CRRFCURB239A00 CRRFCURB240A00 CRRFCURB241A00 CRRFCURB242A00 CRRFCURB243A00 CRRFCURB244A00 CRRFCURB245A00 CRRFCURB246A00 CRRFCURB247A00 CRRFCURB248A00 DIMENSION A 361.11 376.20 385.11 400.20 427.61 439.86 442.70 451.61 454.95 463.
O'-13/16" [21] 0'-3" [76.2] 10'-8 7/8" [3274] 0'-1" [25.4] (CORNER CONNECTIONS AND SPLICE PLATE CONNECTIONS) RETURN BASE RAIL CROSS SECTION TYP ALL BASE RAILS 0'-1 3/4" [44] 4. CROSS SUPPORTS EQUALLY SPACED APPROX 5'-6' APART 3. DIMENSIONS IN [ ] ARE MILLIMETERS. 2. ROOF CURB: 14 GA.[VA03-56] STL. 1. ROOF CURB ACCESSORY IS SHIPPED DISASSEMBLED.
50N ROOF CURB SIZES N, P, Q (75-105 TON NOMINAL CAPACITY) PART NUMBER* CRRFCURB201A00 CRRFCURB202A00 CRRFCURB203A00 CRRFCURB204A00 CRRFCURB205A00 CRRFCURB206A00 CRRFCURB207A00 CRRFCURB208A00 CRRFCURB209A00 CRRFCURB210A00 CRRFCURB211A00 CRRFCURB212A00 CRRFCURB213A00 CRRFCURB214A00 CRRFCURB215A00 CRRFCURB216A00 CRRFCURB217A00 CRRFCURB218A00 CRRFCURB219A00 CRRFCURB220A00 CRRFCURB221A00 CRRFCURB222A00 CRRFCURB223A00 CRRFCURB224A00 DIMENSION A 296.11 311.20 320.11 335.20 356.61 371.70 380.61 395.70 419.36 434.
a48-8745 ACCESSORY PART NUMBER UNIT SIZE NOMINAL TONS 75 ALL 90 STANDARD EFFICIENCY 90 HIGH EFFICIENCY 105 STADARD EFFICIENCY 105 HIGH EFFICIENCY 120 STANDARD EFFICIENCY 120 HIGH EFFICIENCY 130 ALL 150 ALL — — YES YES YES — CRRFCURB287A00 YES — — — CRRFCURB286A00 — YES — YES — YES — — YES YES COND COIL 3V COND COILS 2V ROOF CURB CONDENSER SUPPORT ROOF CURB CONDENSER SECTION 181.50 181.50 181.50 129.50 181.50 129.50 181.50 129.50 181.50 129.50 DIM. D 129.50 — — — 10.62 9.
Performance data COMPONENT PRESSURE DROPS (in. wg) SIZES N, P, Q (75-105 TON NOMINAL CAPACITY) COMPONENT AIRFLOW (cfm) 15,000 19,000 23,000 27,000 31,000 35,000 39,000 43,000 47,000 52,000 High-Capacity Coil (75-90) 0.05 0.10 0.14 0.18 0.22 0.26 0.29 0.32 0.34 0.37 High-Capacity Coil (105) 0.04 0.09 0.14 0.19 0.24 0.28 0.32 0.36 0.40 0.44 Humidi-MiZer® System (75-105) 0.12 0.13 0.15 0.16 0.18 0.21 0.25 0.31 0.38 0.49 Hydronic Coil (75-105) 0.13 0.20 0.28 0.
Performance data (cont) COMPONENT PRESSURE DROPS (in. wg) SIZES R, S, T (120-150 TON NOMINAL CAPACITY) AIRFLOW (cfm) COMPONENT 24,000 28,000 32,000 36,000 40,000 44,000 48,000 52,000 56,000 60,000 High-Capacity Coil (120) 0.10 0.13 0.16 0.19 0.22 0.25 0.28 0.31 0.33 0.36 High-Capacity Coil (130-150) 0.11 0.14 0.17 0.20 0.23 0.26 0.29 0.33 0.36 0.39 Humidi-MiZer® System (120-150) 0.24 0.25 0.26 0.27 0.28 0.30 0.33 0.37 0.43 0.50 Hydronic Coil (120-150) 0.18 0.
Electrical data Please refer to the Applied RTUBuilder software for the unit electrical data. The unit electrical data may also be found in the unit Installation Instructions. MOTOR LIMITATIONS NOMINAL HP BkW MAX BHP MAX BkW 7.5 10 15 20 25 30 40 50 60 75 100 5.60 7.46 11.19 14.92 18.65 22.38 29.84 37.30 44.80 59.50 74.60 8.6 11.5 17.3 22.9 28.7 34.5 45.9 57.4 68.9 86.1 114.8 6.39 8.56 12.89 17.10 21.41 25.71 34.27 42.83 51.41 64.25 85.67 MAX AMPS (EA) 460 V 575 V 12.0 10.0 14.3 12.0 22.0 19.0 28.
Controls Control components The 48/50N Series rooftops use the ComfortLink control system that has been developed for use in Carrier Commercial equipment. The control system monitors all operating conditions in the rooftop unit as well as controlling the compressors, economizers, fans, heat and other devices. It also has the capability of communicating with the Carrier Comfort Network® devices using the CCN protocol and other popular protocols including BACnet, MODBUS, and LonWorks.
controls and provides an additional stage of capacity as well as low load coil freeze protection. The control also integrates the use of an economizer with the use of mechanical cooling to allow for the greatest use of free cooling. When both mechanical cooling and the economizer are being used, the control will use the economizer to provide better temperature control and limit the cycling of the compressors.
Controls (cont) heat capacity based on set point and supply-air temperature. The valve control logic will modulate the heating capacity to match the calculated demand. When the unit is in a HIGH HEAT mode the modulating valve will go to a full open position. Modulating hydronic heat can also be used in a TEMPERING mode.
displayed by the ComfortLink scrolling marquee in parts per million (ppm). Outdoor air cfm control — Minimum space ventilation requirements can also be maintained by applying the minimum outdoor air cfm control option. This option provides an airflow monitoring station at the outside air damper inlet.
Controls (cont) • • • • • 4 to 20 mA signal. It can be connected to terminals 8 and 9 on TB202. Remote Static Pressure Reset Set Point — A remote supply air temperature set point reset can be supported when the controls expansion module is used. This input requires a 4 to 20 mA signal. It can be connected to terminals 6 and 7 on TB202. This input is shared with the Outdoor Air IAQ signal.
• For units connected to the CCN network the user can also display all the unit information including I/O values Maintenance, Configuration, Service, and Set Point data tables • Indoor air quality (IAQ) Variable air volume (VAV) applications The 48/50N Series units are designed to operate in VAV applications. They include a supply fan inverter (VFD) to control the supply fan speed and duct pressure. They are designed to control the leaving-air temperature in cooling to a configurable set point.
Controls (cont) Constant volume and staged air volume space temperature sensor control — If the space temperature operation has been selected using a T55, T56, or T58 sensor then the following logic will be used to control the operation of the unit. If a space temperature is used then a wire jumper must be added between R, W1, and W2. If a remote occupancy control method has been selected then the input must first be closed for the unit to go into Heat, Vent or Cooling mode.
mode the control will energize the heat interlock relay which will signal the terminals to open to the heating position. Note that for the linkage systems the interlock relay connection is not required. Once the Heat mode is enabled, the heat capacity will be controlled by the return air temperature set point. Heating will continue until the return temperature set point is satisfied.
Controls (cont) motor, integrated gas control (IGC) board, 2-stage gas valve, manifold, and safeties. The modulating system incorporates an additional modulating gas valve and modulating gas control. For 2-stage heat control the systems are operated in parallel. For example, when there is a call for first stage heat, both induced-draft motors operate, both gas valves are energized, and both IGC boards initiate spark.
Application data Ductwork — Secure vertical discharge ductwork to the roof curb. Interior installation may proceed before the unit is set in place on the roof. For horizontal discharge applications, attach the ductwork to the flanges on the side of the unit. Vertical discharge units equipped with electric heat require a 90-degree elbow below the unit supply duct connection.
Application data (cont) LOCATION OF COIL TRACKS "J" AUXILIARY COIL LOCATION B AUXILIARY COIL LOCATION — in. UNIT SIZES 48/50N (TONS) N, P, Q (75-105) R, S, T (120-150) 54 HEIGHT B DISTANCE J 12.85 12.
Typical piping and wiring STANDARD UNITS a48-8675 CONDENSATE DRAIN CONNECTION CONTROL WIRING NATURAL GAS ENTRY SUPPLY LINE WITH SHUTOFF MAIN POWER SUPPLY ENTRY 55
460V ONLY POWER SCHEMATIC — SIZE N SHOWN (75 TON NOMINAL CAPACITY) Typical wiring schematics a48-8658 56
460V ONLY POWER SCHEMATIC — SIZES P, Q, R, S, T SHOWN (90-150 TON NOMINAL CAPACITY) a48-8659 57
Typical wiring schematics (cont) CONTROL SECTION — 48/50N UNITS a48-8660 58
CONTROL SECTION — 48/50N UNITS (cont) a48-8661 59
Typical wiring schematics (cont) CONTROL SECTION — 48/50N UNITS (cont) a48-8662 60
MODULATING GAS HEAT SCHEMATIC a48-8663 61
Typical wiring schematics (cont) STANDARD GAS HEAT SCHEMATIC a48-8664 62
ELECTRIC HEAT SCHEMATIC A50-8782 63
Typical wiring schematics (cont) 460-V, 24-V CONTROL SCHEMATIC 64 A48-8665
575-V, 24-V CONTROL SCHEMATIC A48-8666 65
Typical wiring schematics (cont) STANDARD GAS HEAT, 2 MODULE SCHEMATIC A48-8667 66
STANDARD GAS HEAT, 3 MODULE SCHEMATIC A48-8668 67
Typical wiring schematics (cont) STANDARD GAS HEAT, 4 MODULE SCHEMATIC A48-8669 68
STANDARD GAS HEAT, 5 MODULE SCHEMATIC A48-8670 69
Typical wiring schematics (cont) LEGEND FOR TYPICAL CONTROL WIRING SCHEMATICS ACCSY ACC’Y AF AN AO BR C CB CCB CCH CCHR CCN CCT CEM CMR COMP CR CSB CXB DGS DI DPT DTT DUS ECON EQUIP ERV ERVCB ERVTB EVAP EXB EXV FU GND GVR 70 — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — Accessory Accessory Air Foil Analog Anaolog Output Blower Relay Compressor Contactor Compressor Circuit Breaker Control Circuit Breaker Crankcase Heater Crankcase Heater Relay Carrier Comfort Network® Cooling Coil
Guide specifications — 48N units Packaged Rooftop Cooling Unit with Gas Heat and ComfortLink Controls HVAC Guide Specifications — Section 48N2,N3,N4,N5,N6,N7,N8,N9 Size Range: 75 to 150 Tons, Nominal Carrier Model Number: 48N2 (Vertical Supply/Return, Constant Volume [CV] Application, Staged Air Volume [SAV™]) 48N3 (Vertical Supply/Return, Variable Air Volume [VAV] Application) 48N4 (Horizontal Supply/Return, Constant Volume Application, Staged Air Volume) 48N5 (Horizontal Supply/Return, Variable Air Volume
Guide specifications — 48N units (cont) contain a factory-installed nonferrous main condensate drain connection. 9. Top cover of airside section to be sloped to prevent standing water. 10. Units shall be equipped with lifting lugs to facilitate overhead rigging. Lifting lugs shall also be suitable as tie down points. C. Compressors: 1. Fully hermetic scroll type compressors with overload protection and short cycle protection with minimum on and off timers. 2.
G. H. I. J. 10. On-board storage of unit manufacturer's customer user settings, retrievable from the keypad. 11. RS485 communications capability (accessory card source required). 12. Internal thermal overload protection. 13. 5% swinging (non-linear) chokes for harmonic reduction and improved power factor. 14. All printed circuit boards shall be conformal coated.
Guide specifications — 48N units (cont) 6) 7) 8) 9) 10) 11) 12) 13) 74 shall be provided when unit is equipped with modulating gas heat option. Adaptive optimal start shall determine the time unit will commence cooling (or heating or heating for morning warm-up) during the unoccupied mode to ensure occupied space reaches the set point in time for occupied mode.
21) Space Temperature Offset function shall permit occupants to adjust space temperature set point by ±5° F using T-56 space sensor (equipped with sliding scale adjuster). 22) Lead-lag function shall distribute starts between the two refrigeration circuits in an effort to equalize the running time on the two circuits. 23) Condenser-fan cycling control shall maintain correct head pressure down to 32 F. 24) Refrigeration system pressures shall be monitored via pressure transducers.
Guide specifications — 48N units (cont) N. Electrical Requirements: All unit power wiring shall enter unit cabinet at a single location. O. Special Features: 1. Digital Compressor: A digital compressor shall be available on the lead circuit for constant volume and variable air volume configurations. The ComfortLink control system shall be capable of unloading this compressor in an infinite number of steps from 100% of unit capacity down to 50% of compressor capacity. 2.
respectively (ASTM D2247-92 and ASTM D870-92). Corrosion durability shall be confirmed through testing to be no less than 1000 hours salt spray per ASTM B117-90. Coil construction shall be aluminum fins mechanically bonded to copper tubes. 12. Motorized Outdoor Air Damper: a. Package consisting of dampers, actuator, and linkages in conjunction with control system to provide outdoor air. b. Dampers shall be an ultra low-leakage type with blade and edge seals.
Guide specifications — 48N units (cont) 17. Belt Guard: Unit shall be equipped with belt guard on all belt-driven fans. The guard shall completely enclose the drive system and be removable for service. 18. Mixed Air Filters: Unit shall be factory equipped with: a. 4 in. MERV 8 pleated filters having the following characteristics: Efficiency of no less than 30% based on testing per ASHRAE Standard 52 and a minimum average arrestance of 95%. b. 4 in.
25. 26. 27. 28. 29. 30. heating supply air temperature set point. Turndown ratio to be at least 7:1 for the smallest low heat option, ranging up to 18:1 for the high heat options. 2) Full-fire demand heating on heating control command. 3) Tempering heat control, based on userconfigured ventilation supply air temperature set point, to eliminate cold draft conditions with low mixed-air temperatures. b.
Guide specifications — 48N units (cont) 32. 33. 34. 35. 36. 37. 38. 80 k. All factory wiring penetrating through the panel is protected in 'RIGID' type metal conduit. Non-Fused Disconnect: A non-fused electrical disconnect for main unit power shall be factory installed. The disconnect shall be an interlocking through-the-door type. Fused Disconnect: A fused electrical disconnect for main unit power shall be factory installed. The disconnect shall be an interlocking through-the-door type.
45. 46. 47. 48. protect the unit if an abnormal condition is detected. BACnet Communication Option: Shall provide factory-installed communication capability with a BACnet MS/TP network. Allows integration with i-Vu® Open control system or a BACnet Building Automation System. MODBUS Protocol Translator: A controller-based accessory module shall provide CCN access to MODBUS Remote Terminal Unit (RTU) protocol conversion.
Guide specifications — 50N units Packaged Rooftop Cooling Unit with ComfortLink Controls and Optional Electric or Hydronic Heat HVAC Guide Specifications — Section 50N2,N3,N4,N5,N6,N7,N8,N9 Size Range: 75 to 150 Tons, Nominal Carrier Model Number: 50N2 (Vertical Supply/Return, Constant Volume [CV] Application, Staged Air Volume [SAV™]) 50N3 (Vertical Supply/Return, Variable Air Volume [VAV] Application) 50N4 (Horizontal Supply/Return, Constant Volume Application, Staged Air Volume) 50N5 (Horizontal Supply/R
2. Factory rubber-in-shear mounted for vibration isolation. 3. Reverse rotation protection capability. 4. Crankcase heaters shall only be activated during compressor off mode. D. Coils: 1. Evaporator Coil: a. Intertwined circuiting constructed of aluminum fins mechanically bonded to seamless copper tubes. b. Full-face active type during full and part load conditions. c. Coils shall be leak tested at 150 psig and pressure tested at 650 psig. 2. Condenser Coils: a.
Guide specifications — 50N units (cont) G. Outdoor-Air Hood Assembly: Factory-installed motorized outdoor-air damper shall allow intake of up to 100% nominal airflow (on units not equipped with optional economizer). H. [Electric Heating Section:] Electric resistance heaters shall be factory installed, open wire nichrome element type, insulated with ceramic bushings, and shall include operating and safety controls. I.
7) Adaptive optimal stop shall turn off the compressors a preset amount of time before the end of the occupied mode to conserve energy (CV only). 8) Alerts and Alarms: Control shall continuously monitor all sensor inputs and control outputs to ensure safe and proper system operation. Alerts shall be generated whenever sensor conditions have gone outside criteria for acceptability.
Guide specifications — 50N units (cont) 22) Lead-lag function shall distribute starts between the two refrigeration circuits in an effort to equalize the running time on the two circuits. 23) Condenser-fan cycling control shall maintain correct head pressure down to 32 F. 24) Refrigeration system pressures shall be monitored via pressure transducers. Alarms for low pressure, high pressure will be permitted.
P. Electrical Requirements: All unit power wiring shall enter unit cabinet at a single location. Q. Special Features: 1. Digital Compressor: A digital compressor shall be available on the lead circuit for constant volume and variable air volume configurations. The ComfortLink control system shall be capable of unloading this compressor in an infinite number of steps from 100% of unit capacity down to 50% of unit capacity. 2.
Guide specifications — 50N units (cont) respectively (ASTM D2247-92 and ASTM D870-92). Corrosion durability shall be confirmed through testing to be no less than 1000 hours salt spray per ASTM B117-90. Coil construction shall be aluminum fins mechanically bonded to copper tubes. 12. Motorized Outdoor Air Damper: a. Package consisting of dampers, actuator, and linkages in conjunction with control system to provide outdoor air. b. Dampers shall be an ultra low-leakage type with blade and edge seals.
17. Belt Guard: Unit shall be equipped with belt guard on all belt driven fans. The guard shall completely enclose the drive system and be removable for service. 18. Mixed Air Filters: Unit shall be factory equipped with: a. 4 in. MERV 8 pleated filters having the following characteristics: Efficiency of no less than 30% based on testing per ASHRAE Standard 52 and a minimum average arrestance of 95%. b. 4 in.
Guide specifications — 50N units (cont) 25. 26. 27. 28. 29. 30. 90 2) Full output heating on heating control command. 3) Tempering heat control, based on userconfigured ventilation supply air temperature set point, to eliminate cold draft conditions with low mixed-air temperatures. b. SCR heat control option shall consist of: 1) SCR controller capable of ensuring the proper heating rates. 2) Supply air temperature thermistors with duct-mounting base. 3) Limit switch temperature thermistors. c.
32. Non-Fused Disconnect: A non-fused electrical disconnect for main unit power shall be factory installed. The disconnect shall be an interlocking through-the-door type. 33. Fused Disconnect: A fused electrical disconnect for main unit power shall be factory installed. The disconnect shall be an interlocking through-the-door type. 34. 115-Volt Convenience Outlet: A duplex GFCI (ground fault circuit interrupt) receptacle shall be factory mounted in a weatherproof enclosure and wired for a 10amp load.
Guide specifications — 50N units (cont) thermistor. Temperature set point adjustment potentiometer via slide scale shall provide ±5° F adjustment. CO2 sensor shall provide CO2 measurement range of 0 to 2000 ppm. IAQ signal to unit base board terminals shall be 4 to 20 mA. Sensor shall be equipped with an override button for timed override. Sensor must be powered by a separate field-supplied 24-v transformer. 49. Roof Curb: Designed to comply with criteria established by NRCA Guideline B-1986.
