Model 33-DW

A single packaged unit incorporating both inflation fan, backup power source and pre-wired control system. Shipped fully tested, needs only power and fuel connections to be operational. Emergency engine may be deleted in redundant units when multiple units are used on the same structure.

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Standard Features

Base and housing fabricated from heavy gauge galvanized steel.
Top corners are radius to prevent potential fabric damage.
Louvered motor compartment doors.
Heavy duty extrude aluminum back-draft dampers mounted in discharge ducts.
Opposed blade balancing dampers mounted in discharge ducts.
Primed and painted with polyurethane paint.
Lifting eyes at each corner.


Backwardly inclined airfoil bladed wheels exhibit non-overloading horsepower characteristics, low
noise generation and stable performance over the entire pressure curve.
Wheels are dynamically balanced in two-planes.
Bearings are self-aligning with spring lock collars, double row units are installed on the driven end
of the shaft. All bearings have remote grease lines.
Heavy gauge welded construction.

Drives & Motors

Motors are high efficiency ODP type, mounted on adjustable bases, with
“B” V-belt drives to the fans.
Emergency backup engine is industrial grade, mounted on adjustable base, equipped with heavy
duty centrifugal clutch and double “B” V-belt drive to secondary fan.
Available fuels are LP and natural gas. Gasoline and diesel at extra cost.

Control Panel

Enclosure: Carries NEMA 4-12 label.
Indicators: Building pressure gage – Status lights for control power and building pressure.
Switches & modes of operation, Primary fan: ON – Off,
Secondary Fan: AUTO.- OFF – ON,
Heat: ON – OFF, Emergency engine: Test – AUTO – MAINTENANCE.