B.
Access

 (1)  
Location Zone
 153 Aft cargo compartment (Left)

 NOTE: The relief valves are installed on the airplane skin.
____ This test can only be done from outside the airplane.
 C. Do the relief valve test.
 NOTE:____This test can only be done on one valve at a time. Do the test on the upper relief valve, then do the test again on the lower relief valve.
 S 482-034
 (1)  
Connect the test equipment to the applicable (upper or lower) relief valve.

 (a)  
Make sure all the valves on the test equipment are closed.

 (b)  
Connect the air pressure source to the quick-disconnect air connection on the vacuum tank assembly.

 (c)  
Make sure the vacuum regulator valve on the vacuum tank assembly is turned fully clockwise.

 (d)  
Adjust the air control valve until the indication on the pressure gage is 70 (+10/-10) psi.

 (e)  
Adjust the vacuum regulator valve until the differential pressure is approximately 2.0 psi.

 NOTE: Turn the vacuum regulator valve counter-clockwise to
____ increase the vacuum (differential pressure). The arrow on the vacuum regulator valve indicates an increase of pressure not vacuum.
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 (f)  
Install the static port adapter to the remote sensor port on the airplane fuselage. 1) Make sure the plunger is in the center hole of the port and

 that the adapter is over all of the port.

 (g)  
Open the remote sensor valve to the static port adapter.

 CAUTION: HOLD THE VACUUM HEAD ASSEMBLY AGAINST THE AIRPLANE
_______ FUSELAGE AS YOU DO THE TEST. THE VACUUM HEAD CAN BE DAMAGED IF IT FALLS TO THE GROUND WHEN THERE IS NO VACUUM.
 (h)  Put and hold the vacuum head assembly over the applicable relief valve and open the vacuum head assembly valve. 1) Make sure the vacuum head assembly is sealed to the
 airplane skin.
 S 732-035
 (2)  Do the remote sensor test.
 CAUTION: DO NOT INCREASE THE VACUUM FASTER THAN THE RATES SHOWN.
_______ IF YOU INCREASE THE VACUUM FASTER YOU CAN CAUSE DAMAGE TO THE RATE GUAGE ON THE VACUUM TANK.
 (a)  Adjust the vacuum regulator valve to increase the differential pressure at these rates: 1) When the differential pressure is less than 8.70 psig,
 apply the vacuum at a rate not more than 6000 feet per minute (3.00 psig/min) 2) When the differential pressure is 8.70 - 9.05 psig, apply the vacuum at a rate of 4000 - 5000 feet per minute (2.00 -
2.50 psig/min).
 (b)  Make sure the pressure relief valve opens at a differential pressure of 8.95 |0.10 psig.
 NOTE: The pressure that the relief valve opens is seen on
____ the differential pressure gage when the needle stops, and then starts to decrease.
 (c)  
If the pressure relief valve opens at a differential pressure more than 9.05 psig, make sure that there are no leaks at any of the tubing connections on the vacuum tank assembly.

 (d)  
Adjust the vacuum regulator valve until the differential pressure is approximately 2.0 psig at a rate not more than 4.0 psig/min.

 S 732-036
 (3)  
Do the integral sensor test.

 (a)  
Close the remote sensor valve.

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 (b)  
Adjust the vacuum regulator valve to increase the differential pressure at the rates that follow: 1) When the differential pressure is 0 - 9.00 psig, apply the

 vacuum at a rate not more than 5.00 psig/min. 2) When the differential pressure is 9.00 - 9.57 psig, apply the vacuum at a rate not more than 2.00 psig/min.

 (c)  
Make sure the pressure relief valve opens at a differential pressure of 9.42 |0.15 psig.
　
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