The Twin Gamma Ultra Series of Mixed-Flow roof fans have been designed for use in commercial ducted exhaust applications. Incorporating twin vertical discharge fans, the unit provides 100% stand-by capacity.

These compact and low profile units are fitted with bird-mesh to prevent the entry of birds and vermin into the ducting or building.

They are available in 5 sizes, extending from 315 to 500mm diameter.

Features

• Robust, lightweight construction.
• Choice of speeds available.
• Compact, low profile design.
• Designed for vertical exhaust applications.
• Backdraft-shutters are an optional extra (See special note).
• Can be mounted at angle up to 30°.
• Most 3-phase motors are 2-speed star/delta design

Note: Pressure loss across the shutter is now included in the performance curves.

Construction
Cowls are UV-stabilised plastic. Impellers are Mixed-Flow design and made from high performance injection moulded composite material. Steel components have a corrosion resistant finish. Bird-mesh guards are fitted as standard.

Motor

Type - external rotor, squirrel cage induction motor

Electricity supply - 230V, single and 415V, three-phase, 50Hz

Bearings - sealed-for-life, ball

Speed-controllable using electronic or auto-transformer controllers

All three-phase units are fitted with 2-speed star/delta design motors

Internal Protection
Thermal protection is supplied as standard on all motors

Testing
Air flow tests based on ISO5801
Noise tests based on ISO13347-3

Special Note

Backdraft shutters are offered as an optional extra, but are essential to prevent short circuiting and ensuring proper performance of the product. Due to this, the backdraft shutter effect on the products performance is included in the performance curves. This is to ensure accurate selections to allow reliable and predictable on-site performance. There is no longer a need to add losses due to the backdraft shutter as is required with single Gamma models.

The roof ventilators shall be of the Twin Gamma Ultra Series vertical exhaust type as designed and manufactured by Fantech Pty. Ltd. They shall provide dual fan vertical discharge to provide a 100% stand-by capacity and be of the model numbers shown on the schedule/drawing.

Impellers shall be made from high performance injection moulded composite material. They shall be Mixed-Flow design and driven by speed-controllable external rotor motors with integral thermal overload protection.

The windband shall be of the vertical exhaust design and formed from plastic. Steel components shall be corrosion protected.

All performance data shall be for a complete assembled unit based on ISO5801 for air flow and ISO13347-3 for noise.