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Product Details

The Reznor’s Model CAUA Indoor/Vertical Split System Air Handler
Model CAUA vertical (upflow) split system can provide efficient heating, cooling and/or makeup air, with heating sizes ranging from 150 to 400 MBH and cooling capacities of 5 to 15 tons. Air flow volume can range between 1,600 to 6,580 cfm. The unit can be fueled by either natural gas or propane. It can be arranged for power-venting or separated combustion. A cased cooling coil is available with either a 1/3 – 2/3 or a 50/50 split circuitry.
The 1/3 – 2/3 circuitry is compatible with the Reznor MASA condensing unit.
These units provide a conditioned environment using return and/or outside supply air. With the addition of the optional makeup air burner (Options AD4), Model CAUA can allow for up to 100% outside supply air. An optional mixing box can be installed on the rear of the unit to provide outside and return air dampers with controls including an economizer.

The top of the unit has a discharge opening with flanged duct connection. A screened discharge air plenum can be added for 2, 3 or 4 side air discharge. A high air velocity discharge plenum is available for use with cased cooling coil.

Model CAUA can be installed in a mechanical room or closet where conventional horizontal systems may not fit. Most sizes will easily fit through a 3’ doorway. The larger sizes will fit through double doors. A single unit can be used for retail or light commercial applications instead of “twinned” residential units. Conversely, when the optional screened inlet base is coupled with the discharge air plenum, Model CAUA can be floor mounted in a large space and used and an effective air turnover (destratification) system.

The standard direct drive motor assembly is capable of handling up to 1” w.c. of external static pressure on all sizes. An optional belt drive motor is capable of handling up to 1.5” w.c. of external static pressure on sizes 150 and 200, and 2” WC on sizes 250-400.

Standard heating features include a tubular aluminized steel heat exchanger, a removable burner rack, and centrifugal blower(s). The burner rack is an assembly of inshot burners designed to provide controlled flame stability without lifting or flashback. Standard controls include a single-stage gas valve; direct spark ignition with 100% shutoff; a direct-drive blower motor; a power venter; a combustion air pressure switch; and a safety limit switch. Operation is controlled by an integrated circuit board that includes an LED diagnostic indicator light. The
circuit board monitors heater operation and indicates normal operation as well as identifying any abnormalities in the control functions.

As a separated-combustion unit, combustion air is drawn from the outdoors and vented to the outdoors by using an approved vent/combustion air intake concentric adapter kit. As a power-vented unit, air for combustion is taken from the space where the heater is installed and vented outside using an optional vent cap.

Model CAUA Series units have a five (5)-year limited warranty against defective operating components and a ten (10)-year limited warranty on the heat exchanger. This equipment is design-certified by the Canadian Standards Association (CSA) for installation in the U.S. and Canada.


Perfect for tight mechanical rooms
Replace the practice of “Twinning” two residential furnaces with a single Supply for gas, electric power, supply & return duct plenums and venting
Provides more capacity for heat and can introduce outside air for makeup air to the space.

Standard Features:
● Orifices for natural gas
● Centrifugal blower
● Burner rack with inshot burners
● Direct ignition with 100% lockout
● Single-stage combination gas valve
● 230/1/60 supply voltage
● 230 volt, open/dripproof, direct-drive blower motor with internal overload protection
● Tubular aluminized steel heat exchanger
● High temperature limit control
● Pressure switch to verify vent flow
● Integrated circuit board with LED diagnostic indicator light
● 24-volt control voltage transformer
● Insulated indoor cabinet with pre-coat RAL 9001 white paint finish
● Vertical discharge outlet with duct flange
● Corner indicators to allow the installer to customize location of the return air opening (either rear, right side, left side, or bottom)
● Front service access
● Choice of power-vented, separated-combustion or power-vented only installation*

● Discharge plenum
● Orifices for propane gas
● Orifices for high altitude (2001-9000 ft)
● Tubular stainless steel heat exchanger
● Makeup air burner
● Two-stage combination gas valve
◊ Two-stage with ductstat
● Adjustable belt drives for up to 2.0″ ESP with open drip-proof or totally enclosed motors (motors meet EISA specifications for efficiency)
● 208 single phase supply voltage
● 208/230/460/575 three phase supply voltage
● Economizer controls

● Model ACU cased cooling coil
◊ R410A refrigerant
◊ Cooling range from 60 to 180 MBH (5 to 15 tons)
◊ Sizes 90 to 180 can be 1/3-2/3 or 50/50
◊ 1/3 -2/3 circuits (compatible with Reznor MASA condensing unit)
● Horizontal or vertical concentric adapter combustion air/vent kit*
● Inlet air base
● Filter cabinet with 2″ filters (assembly required)
● Mixing box with damper(s) with selection of actuators and controls with or without filters (factory-assembled)
● Vibration isolation pads
● Thermostat
● Thermostat guard
● Vent cap*
● Manual gas valve
● Gas conversion kits

*IF the heater is being installed as a separated-combustion power-vented unit, selection of either a horizontal or vertical concentric adapter combustion air/vent kit is required. Or, IF the heater is being installed as a power-vent only unit, a vent cap is required.

Adjusted pressure drop is external ductwork plus any specified options.