Keep NBC fan fanning

PS: The Preventive Maintenance Monthly, April, 2005

Dear Editor,

The NBC centrifugal fan, NSN 4140-01-23H-8170, that's used on many shelters doesn't have much protection from the elements. It has no gaskets or seals to seal out dust and moisture. Operating in the desert, the fan can quickly fill with sand and shut down. Moisture can kill it just as quickly in a rainy area. If the NBC centrifugal fan stops working, the van loses the positive pressure that shuts out chemical agents in an attack.

A little PM and synthetic rubber adhesive, NSN 8040-00-843-0802, can give NBC centrifugal fans and shelter crews much more protection.

Remove the fan assembly from its mounting bracket and then remove the heat sink assembly from the fan assembly. Be careful not to damage the wire harness connecting the heat sink to the fan. Use compressed air to blow out any sand in the fan. Reinstall the heat sink.

Seal any seams and openings with the synthetic rubber adhesive. Reinstall the fan assembly after the adhesive is thoroughly dry. See TACOM-SBC maintenance advisory message 04-013-014 for more info.

Crews operating in Iraq should remember that the NBC centrifugal fans are designed to run in temperatures up to 120[degrees]F. But in hotter weather, the fans may burn out. If it's over 100[degrees], rig a shade for the fan to keep it out of direct sunlight.

James Pratt

Ft Huachuca, AZ

Editor's note: We are a fan of your suggestions. All shelter crews should immediately blow out and seal NBC centrifugal fans. Some of the shelters that use the fan are the AN/TSM-191(V)2 electronic shop, AN/TSQ-179(V) Target Acquisition Subsystem, Theater High Altitude Air Defense, and the AN/TPQ-36 and AN/TPN-31 radar sets.

If you have any questions about how to do this, contact TACOM-SBC's Steve Sutton at DSN 793-1687/(309) 782-1687 or email steve.sutton@us.army.mil