Proper fan installation is necessary to optimize performance. The following points outline installation techniques to help acheive optimum performance. For existing construction, depending on the building's structure and the ability to access the ducts, you many not be able to use all of these techniques, however, the more techniques used, the better the performance you can expect from your ventilation fan. In new construction where the walls and ceilings are open, with proper planing, applying these techniques can be relatively easy.

IMPORTANT:
In order to reduce elbows and optimize fan performance, install the fan with the exhaust port pointed in the direction of the termination point. Be sure to use the duct diameter size specified for the selectd fan. Reducing the duct diamter (at any point in the duct run) may create substantial static pressure and reduce the fan's performance by as much as 90%.

Elbows and bends should be avoided as much as possible. However, the fact is that many installations require at least one elbow. There are two precautions you can take when installing elbows to achieve optimum airflow.

First, allow a 2 - 3 foot straight run out of the fan before the first elbow. This allows airflow momentum to build before passing through the first elbow. An installation that has a 90-degree elbow immediately after the fan exhaust port will cause air to flow back into the fan. This will reduce fan performance and increase noise.

Second, use a long radius angle to help ensure optimum airflow and minimum airflow noise.

The shortest smooth, inner surface duct with the least number of elbows will provide optimum fan performance.

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