RN SERIES Packaged Rooftop Units, Heat Pumps, & Outdoor Air Handling Units Installation, Operation, & Maintenance WARNING FIRE OR EXPLOSION HAZARD Failure to follow safety warnings exactly could result in serious injury, death or property damage. WARNING o Do not store gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance Improper installation, adjustment, alteration, service, or maintenance can cause serious injury, death, or property damage.
Table of Contents Safety .............................................................................................................................................. 8 RN Series Feature String Nomenclature ....................................................................................... 13 General Information ...................................................................................................................... 24 Codes and Ordinances ..................................................
Checking Liquid Sub-Cooling .............................................................................................. 76 Checking Evaporator Superheat............................................................................................ 76 Adjusting Sub-cooling and Superheat Temperatures............................................................ 77 Gas Heater Instructions .............................................................................................................
Index of Tables and Figures Tables: Table 1 - Electric and Gas Heating Capacities ............................................................................. 28 Table 2 - A Cabinet Unit Clearances ............................................................................................ 30 Table 3 - B Cabinet Unit Clearances ............................................................................................ 30 Table 4 - C Cabinet Unit Clearances .................................................
Table 42 - 55, 65, and 75 ton Unit Filters ..................................................................................... 98 Table 43 - 90-140 ton Unit Filters ................................................................................................ 99 Table 44 - 6-8 and 10 ton Energy Recovery Wheel Filters .......................................................... 99 Table 45 - 9 and 11-15 ton Energy Recovery Wheel Filters ........................................................
Figure 35 - RET with Pin in Groove 4 .......................................................................................... 73 Figure 36 - Fan HUB and RET Castings ...................................................................................... 73 Figure 37 - Assembled Fan ........................................................................................................... 74 Figure 38 - Back of the Fan .........................................................................................
Safety Attention should be paid to the following statements: NOTE - Notes are intended to clarify the unit installation, operation, and maintenance. CAUTION - Caution statements are given to prevent actions that may result in equipment damage, property damage, or personal injury. WARNING - Warning statements are given to prevent actions that could result in equipment damage, property damage, personal injury or death.
WARNING FIRE, EXPLOSION OR CARBON MONOXIDE POISONING HAZARD Failure to replace proper controls could result in fire, explosion, or carbon monoxide poisoning. Failure to follow safety warnings exactly could result in serious injury, death or property damage. Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this appliance. WARNING During installation, testing, servicing, and troubleshooting of the equipment it may be necessary to work with live electrical components.
WARNING WARNING UNIT HANDLING WATER PRESSURE To prevent injury or death lifting equipment capacity shall exceed unit weight by an adequate safety factor. Always test-lift unit not more than 24 inches high to verify proper center of gravity lift point to avoid unit damage, injury or death. Prior to connection of condensing water supply, verify water pressure is less than maximum pressure shown on unit nameplate.
CAUTION Do not clean DX refrigerant coils with hot water or steam. The use of hot water or steam on refrigerant coils will cause high pressure inside the coil tubing and damage to the coil. CAUTION Door compartments containing hazardous voltage or rotating parts are equipped with door latches to allow locks. Door latch are shipped with nut and bolts requiring tooled access. If you do not replace the shipping hardware with a pad lock always re-install the nut & bolt after closing the door.
4. Provide adequate combustion ventilation air to the furnace. If a vent duct extension is used, a class III approved vent is required. See the Locating Units and Gas Heating sections of the Installation section of the manual. 5. Always install and operate furnace within the intended temperature rise range and duct system external static pressure (ESP) as specified on the unit nameplate. 6. The supply and return air ducts must be derived from the same space.
RN Series Feature String Nomenclature BASE MODEL SERIES AND GENERATION RN UNIT SIZE 006 = 6 ton Capacity 007 = 7 ton Capacity 008 = 8 ton Capacity 009 = 9 ton Capacity 010 = 10 ton Capacity 011 = 11 ton Capacity 013 = 13 ton Capacity 015 = 15 ton Capacity 016 = 16 ton Capacity 018 = 18 ton Capacity 020 = 20 ton Capacity 025 = 25 ton Capacity 026 = 26 ton Capacity 030 = 30 ton Capacity 031 = 31 ton Capacity 040 = 40 ton Capacity 050 = 50 ton Capacity 055 = 55 ton Capacity 060 = 60 ton Capacity 065 = 65 ton
RN Series Feature String Nomenclature Model Option A: COOLING/HEAT PUMP A3: COIL COATING 0 = Standard 1 = Polymer E-Coated Evap. and Cond. 2 = Stainless Steel Casing Evap and Cond 8 = Polymer E-Coated Cond. 9 = Polymer E-Coated Cooling Coil A = Stainless Steel Evap. Coil Casing + Polymer ECoated Cond. Coil B = Stainless Steel Casing Cond & Polymer ECoated Cooling Coil C = Stainless Steel Casing Cond.
RN Series Feature String Nomenclature B2: HEATING DESIGNATION 0 = No Heating 1 = Heat 1 2 = Heat 2 3 = Heat 3 4 = Heat 4 6 = Heat 6 7 = Heat 7 8 = Heat 8 9 = Heat 9 A = Heat A B = Heat B C = Heat C D = Heat D E = Heat E F = Heat F G = Heat G H = 1 Row Coil J = 2 Row Coil K = Heat K L = Heat L M = Heat M N = Heat N P = Heat P Model Option B: HEATING B3: HEATING STAGING 0 = No Heating 1 = 1 Stage 2 = 2 Stage 3 = 3 Stage 4 = 4 Stage 5 = 5 Stage 6 = 6 Stage 7 = 7 Stage 8 = 8 Stage 9 = Modulating Gas/SCR Elect
RN Series Feature String Nomenclature Feature 1: RETURN/OUTSIDE AIR 1B: RETURN/EXHAUST AIR BLOWER CONFIGURATION 0 = Standard – None A = 1 Blower + Standard Eff. Motor C = 1 Blower + Premium Eff. Motor D = 2 Blowers + Premium Eff. Motors E = 1 Blower + Premium Eff. + 1 VFD F = 2 Blowers + Premium Eff. + 1 VFD G = 2 Blowers + Premium Eff. + 2 VFDs 1C: RETURN/EXHAUST AIR BLOWER 0 = Standard - None A = 12”x9” Forward Curved B = 15” Backward Curved Plenum C = 18.
RN Series Feature String Nomenclature Feature 2: OUTSIDE AIR CONTROL Feature 3: HEAT OPTIONS 0 = Standard - None A = 3 Position Actuator - Sensible Limit B = 3 Position Actuator - Enthalpy Limit C = Fully Modulating Actuator - Sensible Limit D = Fully Modulating Actuator - Enthalpy Limit E = DDC Actuator F = Constant Volume Outside Air G = Options A + F H = Options B + F J = Options C + F K = Options D + F L = Options E + F M = 3 Pos. Act. - Sensible Limit + CO2 Override N = 3 Pos. Act.
RN Series Feature String Nomenclature Feature 5: SUPPLY AIR OPTIONS 5A: SUPPLY AIR BLOWER CONFIGURATION 0 = 1 Blower + Standard Eff. Motor A = 2 Blowers + Standard Eff. Motors B = 1 Blower + Premium Eff. Motor C = 2 Blowers + Premium Eff. Motors D = 1 Blower + Premium Eff. + 1 VFD F = 2 Blowers + Premium Eff. + 1 VFD G = 2 Blowers + Premium Eff. + 2 VFDs 5B: SUPPLY AIR BLOWER B = 15” Backward Curved Plenum C = 18.
RN Series Feature String Nomenclature 6C: FILTER OPTIONS 0 = Standard A = Clogged Filter Switch B = Magnehelic Gauge C = Options A + B Feature 7: REFRIGERATION CONTROL 0 = Standard A = 5 Min. Time Delay Relay - Comp. Off B = 20 Sec. Time Delay Relay - Comp.
RN Series Feature String Nomenclature Feature 11: SAFETY OPTIONS Feature 12: CONTROLS 0 = Standard A = Return and Supply Air Firestat B = Return Air Smoke Detector C = Supply Air Smoke Detector D = Options B + C E = Options A + B F = Options A + C G = Options A + B + C H = Remote Smoke Detector Terminals J = Options A + H K = Options B + H L = Options C + H M = Options D + H N = Options A + B + H P = Options A + C + H Q = Options A + B + C + H 0 = Standard A = Low Limit Controls B = Phase and Brown Out
RN Series Feature String Nomenclature Feature 13: SPECIAL CONTROLS 0 = Terminal Block for Thermostat Control D = VAV Unit Controller - VAV Cool + CV Heat E = Constant Volume Unit Controller - CV Cool + CV Heat F = Makeup Air Unit Controller - CV Cool + CV Heat H = Field Installed DDC Controls by Others J = Factory Installed DDC Controls Furnished by Others K = Factory Installed DDC Controls Furnished by Others w/ Isolation relays L = Terminal Block for Thermostat Control with Isolation Relays U = Digital P
RN Series Feature String Nomenclature Feature 18: CUSTOMER CODE 0 = Standard Feature 19: CODE OPTIONS 0 = Standard - ETL U.S.A. Listing B = Chicago - Cool + Gas C = Chicago - Cool + Electric Heat D = Chicago - Cool Only E = Chicago - Gas Only F = Chicago - Electric Heat Only G = Chicago - No Cool + No Heat H = ETL U.S.A. + Canada Listing K = California OSHPD Certification L = Shake Table Cert.
RN Series Feature String Nomenclature Feature 23: TYPE B = Standard - AAON Gray Paint U = Special Pricing Authorization + Special Paint X = Special Pricing Authorization + AAON Gray Paint 1 = Standard Paint + 2 Year Parts Only Warranty 4 = Standard Paint + 5 Year Parts Only Warranty 9 = Standard Paint + 10 Year Parts Only Warranty 23
General Information RN Series packaged rooftop units, heat pumps and outdoor air handling units have been designed for outdoor installation only. Units are assembled, wired, charged and run tested at the factory. Startup and service must be performed by a Factory Trained Service Technician. WARNING Improper installation, adjustment, alteration, service, or maintenance can cause property damage, personal injury or loss of life. Startup and service must be performed by a Factory Trained Service Technician.
Installation of RN Series units must conform to the ICC standards of the International Mechanical Code, the International Building Code, and local building, plumbing and waste water codes. In the absence of local codes installation must conform to the current (United States) National Fuel Gas Code ANSI-Z223.1/NFPA 54 or the current (Canada) National Fuel & Propane Installation Code CSA B149.1 or B149.2, and Mechanical Refrigeration Code CSA B52.
Packaged Direct Expansion (DX) Units WARNING COMPRESSOR CYCLING 5 MINUTE MINIMUM OFF TIME To prevent motor overheating compressors must cycle off for a minimum of 5 minutes. 5 MINUTE MINIMUM ON TIME To maintain the proper oil level compressors must cycle on for a minimum of 5 minutes. Figure 1 - Lockable Handle The cycle rate must not exceed 6 starts per hour. The warranty card must be completed in full and returned to AAON not more than 3 months after unit is delivered.
Never cut off the main power supply to the unit, except for servicing, emergency, or complete shutdown of the unit. When power is cut off from the unit crankcase heaters cannot prevent refrigerant migration into the compressors. This means the compressor will cool down and liquid refrigerant may accumulate in the compressor. The compressor is designed to pump refrigerant gas and damage may occur when power is restored.
Should overheating occur with a gas heat exchanger, or the gas supply fail to shut off, shut off the manual gas valve to the furnace before shutting off the electrical supply. Prolonged overheating of the heat exchanger will shorten its life. If unit has not been selected as a 100% outside air unit (makeup air unit) the return air duct must be sealed to the unit and the return air temperature must be maintained between 55F and 80F.
Wiring Diagrams Unit specific wiring diagrams are laminated and affixed inside the controls compartment door. Condensate Drain Pan Unit requires drain traps to be connected to the condensate drain pan of the unit. The 625 and 30 ton units include one drain pan connection and the 26 and 31-140 ton units include two drain pan connections. Condensate drain pipes or p-traps for each connection are factory supplied and shipped loose in the controls compartment for field installation.
vent outlet shall be greater than 12” off the ground/roof. Installation AAON equipment has been designed for quick and easy installation. Locating Units The curb should be mounted first and must be located so that duct connections will be clear of structural members of the building. Verify rooftop or foundation can support the total unit weight, including accessory weights.
Table 4 - C Cabinet Unit Clearances Unit Size Location 16-25 and 30 tons Front 48” (Controls Side) Back - (Outside Air) 48” *Left Side *21” Right Side 60” Top Unobstructed *Units with a water-cooled condenser or chilled water coil require 48” of clearance on the left side for service access.
CAUTION All roofing work should be performed by competent roofing contractors to avoid any possible leakage. CAUTION Where the supply or warm air duct passes through a combustible roof, a clearance of 1 inch must be maintained between the outside edges of the duct and combustible material in accordance with National Fire Protection Association Standard No. 90A. Provide flashings or enclosure between structure and roof and all joints must be sealed with mastic roofing to ensure a watertight seal.
Figure 5 - RN Series 6-8 and 10 ton Unit Gasket Locations 33
Figure 6 - RN Series 9 and 11-15 ton Unit Gasket Locations 34
Figure 7 - RN Series 16-25 and 30 ton Unit Gasket Locations 35
Figure 8 - RN Series 26, 31-50, 60, and 70 ton Unit Gasket Locations 36
CAUTION Incorrect lifting can cause damage to the unit. Forks must be perpendicular to the unit and they must be in far enough that the back of the forks are no more than 6” away from the edge of the unit. CAUTION Forklifting the Unit (6-25 and 30 ton) 6-25 and 30 ton units can be lifted using a forklift. 9, 11-25 and 30 ton units must have forks 72” in length or the forks must have 72” fork extensions. 6-8 and 10 ton units must have forks at least 48” in length.
with the outside air hood in the open position. Before lifting unit, be sure that all shipping material has been removed from unit. Secure hooks and cables at all lifting points / lugs provided on the unit. Carefully lower and align the unit with utility and duct openings. Lower the unit until the unit skirt fits around the curb. Some units are designed to overhang the curb. Take care that any recessed base rails fit around the curb. Make sure the unit is properly seated on the curb and is level.
Figure 11 - Lifting Details of a 6-25 and 30 ton Energy Recovery Wheel or Power Return Unit Figure 12 - Lifting Details of a 26, 31-50, 60 and 70 ton Unit 39
Figure 13 - Lifting Details of a 55, 65 and 75-140 ton Unit 40
Duct Connection Note: If outside air will be in contact with the air tunnel base of an A, B or C cabinet unit (6-25 and 30 tons), the unit should include the base insulation option or the base must be field insulated. D and E cabinet (26 and 31-140 tons) units include base insulation standard. CAUTION Do not drill or punch holes in the base of the unit, from inside the unit or from below the unit to attach ductwork. Leaking may occur if unit base is punctured.
Seismic Curb Installation Using a standard curb with a seismic unit will void the certification of the unit. All mounting details listed must be followed to achieve seismic certification. The AAON unit must be certified to ICC-ES AC156 when using a seismic curb for seismic certifications to apply. Any deviations or modifications to the unit or curb will void all seismic certification.
Figure 16 - Seismic Solid Bottom Curb without Filters Cross Section Figure 17 - Seismic Solid Bottom Curb without Filters Detail A Figure 18 - Seismic Solid Bottom Curb without Filters Detail B 43
Figure 19 - Seismic Rigid Mount Curb 44
Condenser Hail Guards 90-140 ton Units Condenser hail guards fold down and become a condenser coil shipping cover on 90-140 ton RN Series units with copper tube and aluminum fin condenser coils. Condenser hail guards must be opened before startup of the unit.
Figure 21 - 90-140 ton Condenser Coil Guard Installation Instructions 2 Outside Air Rain Hood Rain hood must be opened before startup of the unit. Fresh air intake adjustments should be made according to building ventilation of local code requirements. 6-25 and 30 ton Units Remove the two screws at the bottom of the rain hood that secure it in the shipping 46 position. Remove the screws that attach the side pieces of the hood to the top of the hood.
Attach the side pieces to the top of the hood using the provided screws and attached the side pieces to the end of the unit through the flange. Apply silicon caulking along the top and both sides of the rain hood. Take care to seal the top corners where the rain hood attaches to the unit. Figure 22 - 6-25 and 30 ton Closed Rain Hood 26 and 31-140 ton Units Remove the shipping screws from each side of the closed hood. Lift hood outward and attach the sides of the hood to the side of the unit.
Failure to attach and seal the end of unit with the flashings may result in water leakage into the curb. Figure 25 - Factory Supplied End Flashings CAUTION In order to prevent water leakage into the roof curb, the factory provided sheet metal flashings MUST BE attached to the unit base to cover the shipping slots at both ends of the unit. Metal Mesh Filters (6-25 and 30 ton Units) Metal mesh outside air filters require installation of the filter rack on the intake of the rain hood.
Electrical Verify the unit nameplate agrees with power supply. Connect power and control wiring to the unit as shown in Figure I12 and in the unit specific wiring diagram, which shows factory and field wiring and is attached to the inside of the door of the controls compartment. WARNING Figure 27 - Unit Utility Entry Electric shock hazard. Before attempting to perform any installation, service, or maintenance, shut off all electrical power to the unit at the disconnect switches.
without effecting the unit’s agency/safety certification. Supply voltage must be within the min/max range shown on the unit nameplate. Available short circuit current should not exceed the short circuit current rating (SCCR) shown on the unit nameplate. CAUTION Three phase voltage imbalance will cause motor overheating and premature failure. Figure 29 - Front View of Utility Entry and Power Switch from Control Compartment (55, 65 and 75-140 ton Units) Size supply conductors based on the unit MCA rating.
CAUTION Rotation must be checked on all MOTORS AND COMPRESSORS of three phase units. Supply fan, exhaust fan, return fan, and condenser fan motors should all be checked by a qualified service technician at startup and any wiring alteration should only be made at the unit power connection.
Total Wire Distance Allowable = (Quantity of Control Wires) x (Control Wire Distance) Take the total wire distance allowable and divide by the quantity of wires to be connected. This indicates the distance allowable for that size wire. The wiring to the unit must not exceed the total wire distance allowable. If the voltage at the connectors is less than 21 VAC, isolation relays must be installed. If under external control 21 VAC must be field verified.
Table 13 - 55, 65 and 75-140 ton Gas Connections Model Connections Input Option MBH Quantity Size B2 M 800 2 1” NPT N 1600 1-1/2” 2 NPT P 2400 After verifying gas inlet pressure and manifold pressure the service technician must time the gas flow rate through the gas meter with a stopwatch to verify the gas input rate. Figure 30 - RN Series Gas Heat Exchanger Unit nameplate input rate value has been calculated at the altitude where the unit was shipped.
Do not use gas piping smaller than unit gas connections. Natural gas pipe runs longer than 20 feet and propane gas pipe runs longer than 50 feet may require a larger supply pipe than the unit connection size. Some utility companies may also require pipe sizes larger than the minimum sizes listed. Piping Sizing Examples A 100 ft pipe run is needed for a 1080 MBH natural gas heater. The natural gas has a rating of 1000 Btu/ft3 and a specific gravity of 0.6 (Obtain these values from the local gas supplier.
Table 16 - Gas Piping Supports Pipe Size Support Intervals 1/2” to 3/4” Every 6 ft 3/4” to 1” Every 8 ft 1-3/4” or Larger Every 10 ft (Horizontal) 1-1/4” or Larger Every Floor (Vertical) Additional Gas Piping Considerations Local codes will usually require a field provided and installed manual main shutoff valve and union external to the unit. Main shutoff valve should be labeled. A drip leg should be installed near the unit connection to trap sediment and condensate.
Figure 31 - Example 6-25 and 30 ton through the Base Gas Piping Leak Testing All components of gas supply system, including manual shut off valves and the piping in the interior of the unit, should be leak tested with a soap solution before operating the appliance and at least on an annual basis thereafter. DANGER LEAK CHECK GAS PIPE The gas pipe in the unit should be checked for leaks before startup. Leak checking is the responsibility of the installing contractor.
All gas fired heat exchangers are completely tested at the factory before shipment. This will remove nearly all of the oils that have been used in the manufacturing process. However, trace amounts may remain. When performing the initial startup at the jobsite, it is highly recommended that people or any other living animals, which may be sensitive to the residual odors or gases, NOT be present in the conditioned space during the startup.
Refrigerant-to-Water Heat Exchanger Condenser water pump, condenser water piping, cooling tower or geothermal loop, pressure gauges, strainers, piping insulation and all components of the waterside piping must be field installed. Water-Source Heat Pump Applications Water-source heat pump units using 100% outside air must have electric preheat if the application has a potential for operation with air entering the indoor coil below 43°F with a water loop temperature of 70°F.
CAUTION Cleaning the cooling tower or condenser water loop with harsh chemicals such as hydrochloric acid (muriatic acid), chlorine or other chlorides, can damage the refrigerant-to-water heat exchanger. Care should be taken to avoid allowing chemicals to enter the refrigerant-to-water heat exchanger. See Appendix A - Heat Exchanger Corrosion Resistance for more information. Freezing Water in the Heat Exchanger This product contains one or more refrigerant-to-water heat exchangers.
unit can operate without damaging unit components. WARNING WATER PRESSURE Prior to connection of condensing water supply, verify water pressure is less than maximum pressure shown on unit nameplate. To prevent injury or death due to instantaneous release of high pressure water, relief valves should be field supplied on water piping. Supply water connection may require a backflow preventer to prevent supply makeup water from backing up into the public water system.
used as concentrated chemicals can cause corrosion. Never use hydrochloric acid (muriatic acid) or chlorine as it will corrode stainless steel. CAUTION PVC (Polyvinyl Chloride) and CPVC (Chlorinated Polyvinyl Chloride) are vulnerable to attack by certain chemicals. Polyolester (POE) oils used with R-410A and other refrigerants, even in trace amounts, in a PVC or CPVC piping system will result in stress cracking of the piping and fittings and complete piping system failure.
penetrate the roof external to the unit itself. The drain line should be pitched away from the unit at least 1/8 inch per foot. On longer runs an air break should be used to ensure proper drainage. CAUTION Unit should not be operated without a p-trap. Failure to install a p-trap may result in overflow of condensate water into the unit. Draw-through cooling coils will have a negative static pressure in the drain pan area.
Energy Recovery Units CAUTION Installing Contractor is responsible for proper sealing of the water piping entries into the unit Failure to seal the entries may result in damage to the unit and property. Electric Preheat The modulating electric preheat option is designed to temper the incoming outside air to the unit based on an enable control signal and the outside air conditions. A 24VAC enable signal must be provided to the [PHE] terminal to enable the operation of the electric preheat.
proper operation efficiency and building occupant comfort. Normal maintenance requires periodic inspection of filters, the cassette wheel, drive belts, air seals, wheel drive motor, and its electrical connections. seal and wheel. Racking of the unit or cassette during installation, and/or mounting of the unit on a non-level support or in other than the factory orientation can change seal clearances. Tight seals will prevent rotation. Wiring diagrams are provided with each motor.
Confirm that the wheel rotates freely. Apply power to the unit and confirm rotation. Airflow Balancing and Checking High performance systems commonly have complex air distribution and fan systems. Unqualified personnel should not attempt to adjust fan operation, or air circulation, as all systems have unique operations characteristics. Professional air balance specialists should be employed to establish actual operating conditions, and to configure the air delivery system for optimal performance.
adsorb and desorb moisture and also build up so as to reduce airflow. In a reasonably clean indoor environment such as a school or office building, measurable reductions of airflow or loss of sensible (temperature) effectiveness may not occur for several years. Measurable changes in latent energy (water vapor) transfer can occur in shorter periods of time in applications such as moderate occupant smoking or cooking facilities.
ventilators. In each case, it is recommended that the following considerations be addressed: Accessibility The cassette and all its operative parts; i.e.: motor, belt, pulley, bearings, seals and energy transfer segments must be accessible for service and maintenance. This design requires that adequate clearance be provided outside the enclosure. Where cassettes are permanently installed in a cabinet, access to both sides of the cassette must be provided.
Segment Installation & Replacement Wheel segments are secured to the wheel frame by a Segment Retainer which pivots on the wheel rim and is held in place by a Segment Retaining Catch. Diameter Seal Adjustment Segment Retainer To install wheel segments follow steps one through five below. Reverse procedure for segment removal. 1. Unlock two segment retainers (one on each side of the selected segment opening. 2.
center of the wheel and inwards against the spoke flanges. If hand pressure does not fully seat the segment, insert the flat tip of a screw driver between the wheel rim and outer corners of the segment and apply downward force while guiding the segment into place. 4. Close and latch each Segment Retainer under Segment Retaining Catch. 5. Slowly rotate the wheel 180º. Install the second segment opposite the first for counterbalance.
12. Apply power to wheel and ensure that the wheel rotates freely without interference.
Startup (See back of the manual for startup form.) WARNING Improper installation, adjustment, alteration, service or maintenance can cause property damage, personal injury or loss of life. Startup and service must be performed by a Factory Trained Service Technician. WARNING Electric shock hazard. Shut off all electrical power to the unit to avoid shock hazard or injury from rotating parts. During startup, it is necessary to perform routine checks on the performance of the unit.
Figure 32 - Supply Fan Banding Power Return Axial Flow Fans (16-25 and 30 tons) Blade Pitch Angle Setting Instructions Step 1: Determine the new required pitch for the fan blades Use the fan program in AAON ECat. Step 2: Maintain the balance of fan Mark the HUB/RET castings across a single joint, so the fan can be reassembled in the same orientation. 72 Mark the location of any balancing weight.
Bushing Mount Figure 33 - Fan with the HUB on the Top and RET on the Bottom Step 3: Determine the direction of rotation Right, R, is clockwise when facing the discharge side of the fan and Left, L, is counterclockwise when facing the discharge side of the fan. Step 5: Determine the pin location groove Disassemble fan on a flat surface and note in which groove the pin is located.
Step 7: Determine the current blade pitch and the pin location for the new blades Type 5Z Bushing Mount A B Type Rot.
Step 4: Remove the fan blades and replace the pitch pins Pin Groove Figure 39 - Pin Groove Location Pitch Pin Step 5: Replace the fan blades with the pitch pin of the blade in the same groove and reassemble the fan. Replace the blades and assemble the fan making sure to place the blades in their previous blade sockets, to match up the previous orientation of hub plate casings and to replace any balancing weights in their previous locations. Tighten bolts in a cross pattern to 6.7 ft-lbs. of torque.
CAUTION The Clean Air Act of 1990 bans the intentional venting of refrigerant (CFC’s and HCFC’s) as of July 1, 1992. Approved methods of recovery, recycling or reclaiming must be followed. Fines and/or incarceration may be levied for non-compliance. Before Charging Unit being charged must be at or near full load conditions before adjusting the charge. Units equipped with hot gas reheat must be charged with the hot gas reheat valves closed while the unit is in cooling mode to get the proper charge.
Table 25 - Acceptable Refrigeration Circuit Values Air-Cooled Cond./Air-Air Heat Pump Sub-Cooling 12-18°F Sub-Cooling with 15-22°F Hot Gas Reheat Superheat 8-15°F Water-Cooled Cond./Water Source Heat Pump Sub-Cooling 4-8°F Superheat 8-15°F The system is undercharged if the superheat is too high and the sub-cooling is too low Correct an undercharged system by adding refrigerant to the system to reduce superheat and raise sub-cooling.
Table 26 - R-410A and R-22 Refrigerant Temperature-Pressure Chart PSIG PSIG (F) R-410A R-22 PSIG PSIG PSIG (F) R-410A R-22 (F) R-410A R-22 (F) R-410A R-22 (F) R-410A R-22 20 78.3 43.1 50 142.2 84.1 80 234.9 143.6 110 364.1 226.4 140 540.1 337.4 21 80.0 44.2 51 144.8 85.7 81 238.6 146.0 111 369.1 229.6 141 547.0 341.6 22 81.8 45.3 52 147.4 87.4 82 242.3 148.4 112 374.2 232.8 142 553.9 345.9 23 83.6 46.5 53 150.1 89.1 83 246.0 150.8 113 379.4 236.
Gas Heater Instructions Figure 42 - Gas Heater Instructions 79
Condenser Fan Electronically Commutated Motor (ECM) Startup The fan cycling option uses a fan cycle switch to switch between one of the discrete speed inputs (see Table 27) on the motor thus cycling between two preset speeds based upon discharge pressure of the unit. By connecting 24VAC to a single or combination of the yellow, white, or orange wires, the motor will run at the discrete speeds in Table 27.
VFD Controlled Condenser Fan Startup With Customer Provided Unit Controls the VFD’s are factory provided and factory programmed. VFD’s receives input from pressure transducers on each refrigerant circuit and vary the fan speed based on the pressure inputs to maintain a discharge (head) pressure. Standard pressure setpoint is 340 psi for standard air-cooled systems and 400 psi for modulating hot gas reheat air-cooled systems.
Operation Unit operations should be controlled with thermostat, or unit controller, never at the main power supply, except for servicing, emergency, or complete shutdown of the unit. Thermostat Operation Heating Thermostat system switch - "Heat" Thermostat fan switch - "Auto" or "On" Thermostat temperature set to desired point. Cooling Thermostat system switch - "Cool" Thermostat fan switch - "Auto" or "On" Thermostat temperature set to desired point.
Electric Heating Operation When a call for heating (G and W1, W2, etc.) is made the supply blower motors and electric resistance heaters will energize. Heating is accomplished by passing electrical current through a specified amount of resistance heaters which will produce the required heat. On a fault condition the main limit located in the supply air or the auxiliary limit located downstream the supply blower will remove power from all contactors.
Maintenance (See back of the manual for maintenance log) At least once each year, a trained, qualified service technician should check out the unit. Fans, evaporator coils, and filters should be inspected at least monthly. Gas Heating WARNING Once a year, before the unit is in operation for the heating season, a qualified service technician should inspect all flue product carrying areas of the furnace and main burners for continued safe operation.
If induced draft blower/motor assembly has to be replaced, care must be taken to provide an airtight seal between the blower housing and the burner box. Insert heat exchanger into opening so that the back of the main plate is against the unit bulkhead. Gas Heat Exchanger Removal WARNING Electric shock hazard. Shut off all electrical power to the unit to avoid shock hazard or injury from rotating parts. DANGER LEAK CHECK GAS PIPE The gas pipe in the unit should be checked for leaks before startup.
Condenser Fans (6-25 and 30 ton) Condenser fans and motors can be removed and reinstalled as individual assemblies. WARNING Electric shock hazard. Shut off all electrical power to the unit to avoid shock hazard or injury from rotating parts. WARNING Improper installation, adjustment, alteration, service, or maintenance can cause property damage, personal injury, or loss of life. Startup and service must be performed by a Factory Trained Service Technician.
Evaporator Coil (6-25 and 30 ton) WARNING Electric shock hazard. Shut off all electrical power to the unit to avoid shock hazard or injury from rotating parts. Removal Evacuate refrigerant from the systems. Remove the TXV bulbs from the suction lines. Disconnect the suction and liquid line copper connections to the evaporator coil. Remove the evaporator coil. Reinstallation Install the coil in the unit drain pan.
normal flow rate, preferably in a back-flush mode. After cleaning, the heat exchanger must be rinsed with clean water. A solution of 1-2% sodium hydroxide (NaOH) or sodium bicarbonate (NaHCO) before the last rinse ensures that all acid is neutralized. E-Coated Coil Cleaning Documented routine cleaning of e-coated coils is required to maintain coating warranty coverage for fin and tube and microchannel coils. WARNING Electric shock hazard.
chloride remover to remove soluble salts and revitalize the unit. Recommended Coil Cleaner The following cleaning agent, assuming it is used in accordance with the manufacturer’s directions on the container for proper mixing and cleaning, has been approved for use on e-coated coils to remove mold, mildew, dust, soot, greasy residue, lint, and other particulate: Enviro-Coil Concentrate, Part Number HEC01.
Supply Fans WARNING Electric shock hazard. Shut off all electrical power to the unit to avoid shock hazard or injury from rotating parts. CAUTION Blower wheels and bands must be inspected for excessive dust build up periodically and cleaned if required. Excessive dust build up on blower wheels may cause an unbalanced state; leading to vibration and/or component failure. Damages due to excessive dust build up will not be covered under factory warranty.
the inlet. A screw driver or crowbar can be used to help accomplish this. Use the pry slots on the back side of the motor mount. Pull the motor mount to the edge of the blower frame at the opening. Remove the motor mount with the motor and blower wheel attached. Large motors will require more than one person. Care must be taken not to damage the compressors or refrigerant lines when removing the motor and fan assembly.
4. On/Off LED = Alt. G/R Flashing Phase Loss LED = Green 5. On/Off LED = Green Phase Loss LED = Green controller. For more information on the compressor controller, see Emerson Climate Bulletin AE8-1328. Powering up with no voltage present: 1. On/Off LED = Alternating Green/Red Phase Loss LED = Out Going into trip condition after operating conditions were good: 1. On/Off LED = Green Phase Loss LED = Green 2. On/Off LED = Green Flashing Phase Loss LED = Red 3.
pattern according to the capacity demand signal of the system. The following table shows the linear relationship between the demand signal and compressor capacity modulation. The compressor controller protects the compressor against high discharge temperature. Refer to Appendix B Demand Signal (VDC) 1.00 1.44 3.00 4.20 5.00 for the relationship between thermistor temperature readings and resistance values. Table 28 - Demand Signal vs.
filters must point towards the blower.
Feature 6A 0 A B C Table 33 - 50, 60, and 70 ton Pre Filters Quantity / Size Type No Pre Filters 24 / 12” x 24” x 2” Pleated, 30% Eff, MERV 8 6 / 16” x 25” x 1” Metal Mesh, Outside Air with PE or PR, Feature 1A = B, C 4 / 16” x 25” x 1” 12 / 47” x 12” x 5/16” Lint Screen Table 34 - 55, 65, and 75 ton Pre Filters Feature 6A 0 6B A,B,C,F,G,H A A,B,C,F,G,H B A,B,C,F,G,H C A,C C B,F,G,H Quantity / Size No Pre Filters 15 / 20” x 24” x 2” & 5 / 16” x 20” x 2” Type Pleated, 30% Eff, MERV 8 56 / 20”
Feature 6B 0 B C F G H Feature 6B 0 A B C F G H 96 Table 36 - 6-8 and 10 ton Unit Filters Quantity / Size Type 4 / 16” x 20” x 2” with RAB, Feature A2 = Q, R Pleated, 30% Eff, MERV 8 2 / 20” x 20” x 2” and 1/12” x 24” x 2” 4 / 16” x 20” x 4” with RAB, Feature A2 = Q, R Pleated, 30% Eff, MERV 8 2 / 20” x 20” x 4” and 1/12” x 24” x 4” 4 / 16” x 20” x 2” Permanent Filter Frame with RAB, Feature A2 = Q, R Replaceable Media 2 / 20” x 20” x 2” and 1/12” x 24” x 2” Pleated, 65% Eff, MERV 11 4 / 16” x 20” x
Feature 6B 0 B C F G H Feature 6B 0 B C F G H Table 38 - 13 and 15 ton Unit Filters Quantity / Size Type 4 / 20” x 25” x 2” Pleated, 30% Eff, MERV 8 with RAB, Feature A2 = Q, R 6 / 12” x 24” x 2” 4 / 20” x 25” x 4” Pleated, 30% Eff, MERV 8 with RAB, Feature A2 = Q, R 6 / 12” x 24” x 4” 4 / 20” x 25” x 2” Permanent Filter Frame with RAB, Feature A2 = Q, R Replaceable Media 6 / 12” x 24” x 2” Pleated, 65% Eff, MERV 11 4 / 20” x 25” x 4” Pleated, 85% Eff, MERV 13 Pleated, 95% Eff, MERV 14 Table 39 - 16-2
Feature 6B 0 B C F G H Feature 6B 0 B C F G H Feature 6B 0 B C F G H 98 Table 40 - 26, 31, and 40 ton Unit Filters Quantity / Size Type 8 / 24” x 24” x 2” Pleated, 30% Eff, MERV 8 with RAB, Feature A2 = Q, R 16 / 12” x 24” x 2” 8 / 24” x 24” x 4” Pleated, 30% Eff, MERV 8 with RAB, Feature A2 = Q, R 16 / 12” x 24” x 4” 8 / 24” x 24” x 2” Permanent Filter Frame with RAB, Feature A2 = Q, R Replaceable Media 16 / 12” x 24” x 2” 8 / 24” x 24” x 4” Pleated, 65% Eff, MERV 11 with RAB, Feature A2 = Q, R 16
Feature 6B 0 B C F G H Table 43 - 90-140 ton Unit Filters Quantity / Size Type 35 / 18” x 20” x 2” Pleated, 30% Eff, MERV 8 21 / 20” x 24” x 4” & Pleated, 30% Eff, MERV 8 7 / 16” x 20” x 4” Permanent Filter Frame 35 / 18” x 20” x 2” Replaceable Media Pleated, 65% Eff, MERV 11 21 / 20” x 24” x 4” & Pleated, 85% Eff, MERV 13 7 / 16” x 20” x 4” Pleated, 95% Eff, MERV 14 Table 44 - 6-8 and 10 ton Energy Recovery Wheel Filters Feature 1A Quantity / Size Type 1 / 25” x 16” x 4” With Energy Recovery Wheel Exhaus
Table 47 - 26, 31-50, 60, and 70 ton Energy Recovery Wheel Filters Feature 1A Quantity / Size Type 4 / 24” x 24” x 4” With Energy Recovery Wheel Exhaust F, G, H, J, Q, R, S, T, Air Filters, Feature 6A - D, F, G U, V, W, Y, Z, 1, 2, 3 OA - 4 / 24” x 24” x 2” EA - 8 / 16” x 20” x 2” Pleated, 30% Eff, MERV 8 3 / 24” x 24” x 4” With Energy Recovery Wheel Exhaust 4 Air Filters, Feature 6A - D, F, G OA - 3 / 24” x 24” x 2” EA - 6 / 16” x 20” x 2” Table 48 - 55, 65, and 75-140 ton Energy Recovery Wheel Filters Fea
20” 20” 16” 16” Figure 51 - RN Series 6-8 and 10 ton Standard Filter Layout (Viewed from the Upstream Side of the Cooling Coil) 25” 25” 20” 20” Figure 52 - RN Series 9 and 11-15 ton Standard Filter Layout (Viewed from the Upstream Side of the Cooling Coil) 101
20” 20” 20” 25” 25” Figure 53 - RN Series 16-25 and 30 ton Standard Filter Layout (Viewed from the Upstream Side of the Cooling Coil) 24” 24” 24” 24” 24” 24” Figure 54 - RN Series 26, 31, and 40 ton Standard Filter Layout (Viewed from the Upstream Side of the Cooling Coil) 102
24” 24” 24” 24” 12” 12” 12” Figure 55 - RN Series 50-, 60, and 70 ton Standard Filter Layout (Viewed from the Upstream Side of the Cooling Coil) Note: 50-70 ton units include two coils and thus two filter layouts.
20” 20” 20” 20” 20” 16” 24” 24” 24” Figure 57 - RN Series 55, 65, and 75 ton Standard Filter Layout, 4” Filters (Viewed from the Upstream Side of the Cooling Coil) 20” 20” 20” 20” 20” 20” 18” 18” 18” 18” 18” Figure 58 - RN Series 90-140 ton Standard Filter Layout, 2” filters (Viewed from the Upstream Side of the Cooling Coil) 104 20”
20” 20” 20” 20” 20” 20” 20” 16” 24” 24” 24” Figure 59 - RN Series 90-140 ton Standard Filter Layout, 4” Filters and 2” Pre-Filters with 4” High Efficiency Filters (Viewed from the Upstream Side of the Cooling Coil) Replacement Parts Parts for AAON equipment may be obtained from AAON at www.aaonparts.com. When ordering parts reference the unit serial number and part number. AAON Warranty, Service and Parts Department 2424 S. Yukon Ave. Tulsa, OK 74107 Ph: 918-583-2266 Fax: 918-382-6364 www.aaon.
Appendix A - Heat Exchanger Corrosion Resistance Corrosion Resistance of Copper and Stainless Steel in Brazed Plate Heat Exchangers - Points to Measure and Check in a Water Analysis The resistance guide provides the corrosion resistance of stainless steel type AISI 316 and pure Copper (99.9%) in water, to a number of important chemical factors. The actual corrosion is a very complex process influenced by many different factors in combination.
Water Containing Total Hardness (°dH) Nitrate (NO3) Iron (Fe) Aluminum (Al) Manganese (Mn) Chloride Content = 10 ppm = 25 ppm = 50 ppm = 80 ppm = 150 ppm = 300 ppm > 300 ppm Concentration (mg/l or ppm) Time Limits Analyze Before AISI 316 SMO 254 Copper Alloy Nickel Alloy 4.0-8.5 No Limit + + + + + + + + + + + + + + + + + + + + + 0 + 0 + 0 + 0 + + + + + + + + < 100 > 100 < 0.2 > 0.2 < 0.2 > 0.2 < 0.1 > 0.
Appendix B - Thermistor Temperature vs. Resistance Values Deg C -40 -35 -30 -25 -20 -15 -10 -5 0 5 10 15 20 25 30 35 40 45 50 55 60 65 108 Deg F -40 -31 -22 -13 -4 5 14 23 32 41 50 59 68 77 86 95 104 113 122 131 140 149 Resistance (kOhms) 2889.6 2087.22 1522.20 1121.44 834.72 627.28 475.74 363.99 280.82 218.41 171.17 135.14 107.44 86.00 69.28 56.16 45.81 37.58 30.99 25.68 21.40 17.
RN Series Startup Form Date:______________ Job Name:_____________________________________________________________________ Address:______________________________________________________________________ ______________________________________________________________________________ Model Number:_________________________________________________________________ Serial Number:____________________________________________ Tag:_______________ Startup Contractor:_______________________________________________________
Energy Recovery Wheel Assembly Wheel(s) Spin Freely Number 1 2 Check Rotation hp L1 FLA____________ L2 L3 Power Return/Exhaust Assembly Alignment Number 1 2 Check Rotation hp L1 Nameplate Amps________ L2 L3 Outside Air/Economizer Dampers Operation Check Damper Actuator Type: Economizer Changeover Type and Operations: Damper Wiring Check Gears Check Ambient Temperature Ambient Dry Bulb Temperature ________°F Unit Configuration Water-Cooled Condenser No Water Leaks Condenser Safety Check Water Flo
Refrigeration System 1 – Cooling Mode Saturated Line Pressure Temperature Temperature Discharge Suction Liquid Refrigeration System 2 – Cooling Mode Saturated Line Pressure Temperature Temperature Discharge Suction Liquid Refrigeration System 3 – Cooling Mode Saturated Line Pressure Temperature Temperature Discharge Suction Liquid Refrigeration System 4 – Cooling Mode Saturated Line Pressure Temperature Temperature Discharge Suction Liquid Refrigeration System 1 – Heating Mode (Heat Pump only) Saturated Lin
Refrigeration System 4 – Heating Mode (Heat Pump only) Saturated Line Pressure Temperature Temperature Discharge Suction Liquid Sub-cooling Superheat N/A N/A N/A N/A Air-Cooled Condenser Alignment Number 1 2 3 4 5 6 Check Rotation hp L1 Nameplate Amps________ L2 L3 Water/Glycol System 1. Has the entire system been flushed and pressure checked? Yes No 2. Has the entire system been filled with fluid? Yes No 3. Has air been bled from the heat exchangers and piping? Yes No 4.
Electric Preheating Limit Lockout Aux. Limit Lockout Outside Air Temperature Setpoint ________°F Preheat Leaving Air Temperature Setpoint ________°F Stage 1 2 3 4 Amps Stage 5 6 7 8 Amps Maintenance Log This log must be kept with the unit. It is the responsibility of the owner and/or maintenance/service contractor to document any service, repair or adjustments. AAON Service and Warranty Departments are available to advise and provide phone help for proper operation and replacement parts.
Literature Change History May 2007 Update of IOM unit service clearances. Length of front and back clearances from 60” to 48” and length of left and right side clearances from 100” each to interchangeable 48” and 70”. (Note: Units with hydronic heat must have 70” right side access for service.) Gas piping sizes table on page 10 was updated with new gas heater information. November 2007 Update of the IOM Gas Piping Connection Sizes table.
April 2011 Updated the condenser water connection sizes in Table I12 and added Table I13 – SMO 254 Brazed Plate Heat Exchanger Water Connections. June 2011 Updated 2” Pleated 30% efficiency filters from MERV 7 to MERV 8. March 2012 Updated manual to include 55, 65 and 75-140 unit sizes. Instructions for piping gas heat exchanger condensate, if code requires, were added in the gas heating section. Added hot water, steam, and chilled water coil connection sizes.
AAON 2425 South Yukon Ave. Tulsa, OK 74107-2728 Phone: 918-583-2266 Fax: 918-583-6094 www.aaon.com RN Series Installation, Operation & Maintenance R90721 · Rev. B · 140225 It is the intent of AAON to provide accurate and current product information. However, in the interest of product improvement, AAON reserves the right to change pricing, specifications, and/or design of its product without notice, obligation, or liability. Copyright © AAON, all rights reserved throughout the world.
