The Reznor’s Model AEB Indirect Fired Units
Reznor Model AEB indirect fired units are designed for indoor or outdoor installation in industrial and commercial buildings where air turnover (destratification) is desired. These air handlers are suitable for a wide variety of heating, cooling, and makeup air applications.
Air turnover units are ideal for large open space heating, cooling, ventilation and filtration requirements. They are widely used in manufacturing, distribution and warehouse facilities, as well as steel, pharmaceutical, food and merchandise storage facilities. Air turnover units are also very effective at controlling humidity levels in a space.
Model ACB units are shop assembled and wired complete with burner, primary combustion chamber and secondary heat transfer surfaces, mechanical combustion system, propeller and motor assembly, sheet metal casing, controls and safety devices, flame tested at the manufacturer’s plant and shipped as a complete package assembly. Required accessories are mounted in the factory. Units will be split into sections when required for shipping purposes. Model ACB units offer a complete range of sizes for air handling capacities from 3,250 to 150,000 CFM and heating outputs from 200,000 to 6,000,000 BTUH. Units are also available without heating.
The industrial four-pass, continuously welded drum and tube heat exchanger are constructed of 409 or 304 stainless steel. The robust heat exchanger offers 80+% efficiency and unsurpassed longevity. A forced draft industrial burner provides excellent combustion with low maintenance. Flame safeguards, gas regulators and hydraulic main gas safety shut-off valve are standard. An optional power venter is available. In buildings where negative air pressure or contamination occurs, a sealed combustion duct can be installed. Choose from FM or IRI gas trains with hydraulic shut-off valve and controls. A 15:1 modulating gas burner is available. Burners are
available for use with natural gas, propane or fuel oil.
The unit is constructed of a welded structural iron frame, primed with an epoxy rust inhibitor. The cabinet is constructed of G90, 18 gauge metal. An industrial alkyd enamel gray finish is applied. For outdoor units, epoxy finishes or custom coloring can be selected to match a building exterior. Hinged access doors with stainless steel piano hinges, compression latches and safety switches make for easy fan and motor access.
Each heater is equipped with 1, 2, or 3 low noise propeller fans. Each fan consists of 6 air foil blades. Fan assembly is statically and dynamically balanced at the factory. Fans are mounted on a heavy duty, machined and polished solid steel shaft. The fan motor is mounted on a fully adjustable base. Choose from EPACT Compliant ODP, TEFC or premium efficiency ODP motors. Motors are available with spring or RIS vibration isolation. Perforated liners provided on fan section including fan divider partitions. Sound is captured by the liners and muffled in the two inch thick fiberglass insulation.
Safety controls include a flame safeguard relay with LED status, optional ultra-violet flame detection and prepurge cycle. Fan switch, high and low gas pressure switch, differential air proving switch, and a manual reset temperature high limit safety switch are also available.
Air intake is through an expanded metal screen inlet plenum (heating only) open on all four sides. Flat filter racks can be included in the inlet plenum, or a separate V-Bank filter section can be ordered. Pleated filters can be changed out through hinged access doors. Single or multiple opening inlet air plenums are optional (standard with cooling units). Units can be configured for a 20% outdoor inlet opening with motorized damper or a full mixing box with 100% outside air capability. Mixing box has a variety of damper options including: economizer with enthalpy sensor, differential enthalpy R/A and O/A sensor, and low leak aluminum airfoil dampers operated with direct drive actuators. Dampers are to be designed for operation down to -40°F.
An integral outside air plenum can introduce outside air prior to the filters. The plenum casings are constructed the same as the unit and finished to match. Inlet plenum is designed to prevent water from entering the unit. When the plenum is exterior wall mounted, to finish color can be matched to the exterior of the building. A wall mount flange with gasket runs the perimeter of the inlet plenum. The louvered inlet plenum is equipped with expanded metal where necessary.
Direct expansion or chilled water cooling coils available in blow through or draw through arrangements. Units supplied with cooling include the sound attenuation features as standard. Cooling coil plenum consists of double wall construction. The coil section is insulated with 1” or 2” thick fiberglass insulation. Units with cooling sections include discharge air plenum with adjustable supply air grilles. The plenum features a double sloped 304 stainless steel condensate pan with drain. All pans are a minimum 18 gauge 304 stainless steel continuously TIG welded. Multiple coils are stacked vertically and include intermediate drain pans to reduce refrigerant pressure drop and possibility of water carry over. Coils have 0.020 in. minimum copper tube wall thickness. The fins are rippled and made of a minimum of 0.006 in. aluminum sheet. Coils feature (direct expansion interlaced multi-circuit design) (chilled water). Coils are pressure tested to 250 psig to ensure no refrigerant leaks. Coils are designed around 400 CFM per ton. Coil bypass with manual adjustment damper are provided to prevent CFM per ton ratio exceeding 500.
Heating only units have expanded metal screens on discharge, grilles are optional. In addition to natural gas, LP and fuel oil, Model AEB can be fitted for steam, hot water or electric coils for heating. For outdoor units an interior trapezoidal shaped discharge section can be provided to distribute air inside the building. The discharge is double lined with two inch thick insulation and perforated liner. Discharge section acoustically attenuates airborne noise. Diffuser screens are located on the font of the discharge. The discharge plenum is equipped with single or double adjustable air double deflection airfoil type blades.The remote control enclosure can include: 10 point circuit analyzer, return and/or discharge smoke detector(s), and seven day time clock with night stat.
Other optional equipment include: a full OSHA approved service platform for complete access to burner and gas manifold, bearings equipped with automatic greasing canisters.
Standard Features:
● Hinged access doors with stainless steel piano hinges, compression latches and safety switch
● Numbered control wiring, terminal strip and component identification labels
● EEPAC high efficiency fan motor with adjustable 1.5 s.f. V-Belt drive
● Control transformer with service switch and circuit breaker
● All wiring external to control cabinet within BX cable or conduit
● Induced draft blower
● ETL certified ANSI gas train, flame monitoring and safety controls
● Dead front fused disconnect switch
● Spark igniter and flame rectification
● Fan and high limit switch
● Industrial, four-pass, 409 stainless steel primary and secondary heat exchangers
● PowerFlame™ forced draft industrial burner provides excellent combustion with low maintenance
● Fireye™ flame safeguard provides the safest and most reliable flame monitoring available
● Maxitrol™ regulators
● Hydraulic main gas safety shut-off valve
● Standard Dead-front Safety Disconnect Switch
● Welded structural iron frame, primed with epoxy rust inhibitor
● Galvanealed zinc rich “paint grip” 18 gauge sheet metal
● Industrial alkyd enamel machine gray 3 mil thick casing finish
● Expanded metal inlet/discharge screen (recommended for heating applications)
● Two inch thick Insulated casing with perforated “sound trap” liner in fan deck
● Units supplied with cooling include the sound attenuation feature as standard
● Units supplied without heat exchanger include transition section with sound attenuated construction
● Cooling units are provided with adjustable supply air grilles as standard
● Hinged fan/motor access doors
● High efficiency six bladed airfoil turbine props
Factory Installed Options:
● Electric, hot water or steam heating coils
● Sealed combustion duct connection
● Factory Mutual (FM) or Industrial Risk Insurers (IRI) gas train with hydraulic shut-off valve and controls
● 304 stainless steel primary and secondary heat exchangers (or 304 primary with a 409 secondary stainless steel heat exchanger)
● On/off, two stage or full modulation burner forced draft burner
● TEFC, high efficiency or two-speed motors
● Variable frequency drives
● Nema 4 or 12 control enclosure
● Remote control enclosure
● 10 point circuit analyzer
● Return and/or discharge smoke detector(s)
● Sound attenuation
● Automatic greasing canisters
● Vibration isolation; spring or RIS
● Extended grease lines
● Epoxy paint finish
● Special materials of construction
● Automatic Greasing Canisters
● Custom paint color
● Two inch thick insulation with perforated liner in top of discharge section
● Heating unit have expanded metal screens on discharge, grilles
● Low leak aluminum airfoil dampers operated with direct drive actuators.
● Low leak insulated aluminum airfoil dampers designed for operation down to -40°F
● Blades are to be internally insulated with expanded polyurethane foam and thermally broken – the complete blade shall have an insulating factor of R-2.29 and temperature index of 55.
● Automatic greasing canisters for bearings
● Greasing canisters with pump driven microprocessor
Field Installed Options:
● Single or multiple discharge/inlet openings
● 20% outdoor inlet opening with motorized damper
● Full mix box with 100% outside air capability. Available with two position summer/winter ventilation mode or integrated modulating economizer.
● Indoor/outdoor construction
● Flat filters or V-Bank filter section with pleated filters and hinged access doors
● Direct expansion or chilled water cooling coils available in blow through or draw through arrangements
● Mix box section with motorized dampers
● Full occupied/unoccupied seven day programmability
● Complete temperature control packages including DDC interfacing or computer control
● D/X cooling, chilled water, steam, hot water and electric coils
● Seven day time clock with night stat
● Cooling Coil Section
– Double wall construction
– Insulated with (1) (2) inch thick fiberglass insulation.
– The plenum shall feature a double sloped 304 stainless steel, 18 gauge (minimum), continuously TIG welded condensate pan with drain
– Multiple coils shall be stacked vertically and include intermediate drain pans
– Coils constructed of 0.020 in. minimum copper tube wall thickness
– Minimum 0.006 in. thick aluminum sheet fins
– Coil bypass with manual adjustment damper.
● Discharge Section with Cooling Coil
– Double lined with two inch thick insulation and perforated liner in top discharge section
– Sound attenuation in discharge air section
– Minimum 2 in. thick steel blades painted with industrial paint to match unit
– Each blade shall be individually adjustable
– Dual bank of airfoil type blades for vertical and horizontal air diffusion control
● Outside Air Plenum
– Inlet plenum designed to prevent water from entering the unit.
– Exterior wall mounted plenum color finish to match building colors
– Wall mount flange with gasket runs the perimeter of the inlet plenum.
– Inlet plenum with expanded metal
● Integral Service Platform with Ladder
– OSHA approved service platform for complete access to burner and gas manifold
– Service platform includes 12 gauge expanded metal screen and a welded 3 in. structural iron frame
– Four in. high kick plate and locking chains.
– OSHA approved ladder with hand guide rails and concrete securing feet
● Discharge Section
– Trapezoidal shaped discharge section shall be provided to distribute air inside the building (for outdoor units)
– Double lined with two inch thick insulation and perforated liner
– Sound attenuation
– Diffuser screens located on the font of the discharge
– Single or double adjustable air double deflection airfoil type blades.
● Humidification Plenum
– Internal liner constructed of minimum 22 gauge G90 galvanized steel
– Humidifier mounted, wired and tested from the factory.
– Gas to steam microprocessor control
● “Oil Mist” Filtration
– Two stages of filtration
– Primary: flat filter back with Farr ECO™ four inch thich filters with a drain trough connected to common drain pipe
– Secondary: Two inch thick 30% efficient pleated filters.
IMPORTANT: Specifications are subject to change without notice. This guide is intended to provide
specifications and technical information only.
This guide is not intended to be an instruction manual. When installing HVAC Equipment, you must check and conform to all local and national building codes. Improper installation of HVAC Equipment could be dangerous. Consult manufacturer’s installation manual for instructions and
important warnings.