Ventry POSITIVE PRESSURE VENTILATION FANS, Owner'S Manual

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OSITIVE 

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RESSURE 

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ENTILATION  

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effective.  The air will take the path of least resistance.  If you have a lot of windows and doors 
open the air will most likely take a path that isn’t the one you want to remove the smoke. 

Ground Debris Pickup / Maximum Air Volume 

This positive pressure fan is designed to run with the legs partially extended.  By 

extending the legs, two important things are accomplished.  First, running the fan with the legs 
extended eliminates ground debris pickup and ejection which causes propeller damage.  Second, 
the efficiency (air volume) is increased.  Operating the fan close to the ground can reduce the air 
volume significantly.  Raising the fan allows it to draw air from completely around the guard, 
rather than trying to "suck air out of the ground".  We suggest that you raise the fan at least six 
(6) inches.   

Ideally you raise the fan all of the way.  This maximizes the fan performance and makes 

it easier to start.  With the controls up where they are easy to reach firefighter doesn’t have to 
bend way over or kneel to start the fan, minimizing firefighter fatigue. 

Stability

After placing the fan in the desired position, check the fan's stability.  Start the fan while 

stabilizing it with one hand.  Open the throttle all the way and rock the fan from side to side.  
This will let you determine how stable the fan is.  If necessary, adjust leg lengths to achieve a 
stable position.  At this time, inspect the placement of the positive pressure fan and confirm that 
it is not walking.  Some wooden decks and stairways will vibrate and cause the fan to walk.  A 
simple change of the throttle setting can eliminate this problem.  Decreasing the throttle also 
works on slick surfaces. 

Filling the Gas Tank  

Never fill the gas tank with the fan in operation.  Turn off the engine and allow it to cool 

before refueling.  A small spill or miscalculation while filling a running fan can introduce gas 
into the air stream causing a cloud of vaporized fuel to enter a burning structure.  Your 
imagination can picture the result. 

Backdraft Situations

Alternate ventilation techniques are necessary in the case of a backdraft situation and the 

use of a positive pressure fan is not recommended.  After the backdraft situation has been 
rectified the PPV can be used.