Suredraft - Chimney Ventilation

Suredraft chimney and flue improver is a unique cowl made specifically for use on chimneys and flues where hot exhaust gases are expected.
Many chimneys and flues experience occasional backdrafting when winds driving from a specific direction and are interfered with by nearby buildings, trees or natural topography. This is a very uncomfortable experience for house occupants as smoke is driven back into the home. Poor chimney design is also a cause of backdrafting but there is no easy solution in this case.
Suredraft chimney and flue improver is a unique cowl made specifically for use on chimneys and flues where hot exhaust gases are expected. The product utilises an internal heat shield to protect the bearing and incorporates an external aluminium heat sink to also control the bearing temperature. The Tandaco bearing is packed with heat tolerant grease.
Suredraft prevents downdraft by causing a positive updraft in the flue or chimney. It is important that the turbine be well exposed to the wind to minimise eddies developing on the leeward side.
When installing Suredraft on chimneys a special plate is available to attach the Suredraft 300. Smaller sizes should not be used for chimneys. Standard colour is mill aluminium although powdercoat colours can be arranged for special orders.
TECHNICAL DIAGRAM

The product utilises an internal heat shield to protect the bearing and incorporates an external aluminium heat sink to also control the bearing temperature. The Tandaco bearing is packed with heat tolerant grease.
DIMENSIONS
| MODEL | A (mm) | B (mm) | ØC (mm) | ØD (mm) | Throat Area (m²) | Weight (kg) |
|---|---|---|---|---|---|---|
| SD150 | 324 | 175 | 155 | 329 | 0.0189 | 2.2 |
| SD250 | 399 | 230 | 257 | 420 | 0.0159 | 3.2 |
| SD300 | 399 | 230 | 308 | 474 | 0.0745 | 3.8 |
Tolerances:
Size +/- 2mm
Weight +/- 0.1kg



