See also:

Tips and Troubleshooting Chart
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Weight-Distributing Hitches and Weight Carrying Hitches
A. Body-to-Ground Distance B. Front of Vehicle When using a weight-distributing hitch, the hitch must be adjusted so that the distance (A) remains the same both before and after coupling the trail ...

Manual Operation
The air delivery mode or fan speed can be manually adjusted. (Fan Control): Press to increase or decrease the fan speed. Pressing or while in automatic control places the fan speed under manual ...