Pressurization Issues-P337G
 

Cabin pressurization works fine until you get 1.0 psi pressure and then the cabin rate fluctuates from a plus to minus 1000 fpm indication, hard on the ears.
The shop inspected the outflow and safety pressurization valves, no defects found. They disconnected the controller line at the outflow valve and flew the a/c. The cabin pressurized to 3.2psi with no fluctuations. The shop seem to think the controller has some issues. Any thoughts or information where i can sent the controller to be bench tested/repaired.Thanks Joe

It definitely sounds like a problem with the controller. When I purchased my t337g the pressurization wasn't working. It turns out the plastic line to the controller was kinked; straightening the line fixed the whole system. Perhaps your controller needs to be cleaned or adjusted.

Have you read the cessna pressurization "student workbook"? I tried uploading the pdf just now but it failed for some reason. It has some useful information and diagrams. If you can't find it elsewhere, I will find another way to upload it.

dd

Try this pdf here:

http://www.aeroelectric.com/Referenc...20Workbook.pdf

Very good manual!

Thanks for the information, Joe

Your a gentlemen and a scholar, thanks for posting the manual, great info!