NOTE: Do not remove the ram-air duct or the header.
____
 S 486-016
 (5)  
Connect the test equipment to the cap assemblies.

 S 486-071

 (6)  
Install the cap assembly and the seal on each duct opening of the secondary heat exchanger.

 G. Do the Leak Check (Flow Rate Procedure)
 S 796-017
 (1)  Slowly apply 30 psig (207 kPa gage) pressure to the secondary heat exchanger.
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 S 796-058
 (2)  
Make sure there are no leaks around the cap assemblies.

 S 796-018

 (3)  
Slowly increase the pressure to 58.5 - 61.5 psig
 (404 - 424 kPa gage).

 S 796-051

 (4)  
Make sure there are no leaks around the cap assemblies.

 S 796-052

 (5)
For 2 minutes, make sure the flowmeter does not read more than

 2.0 pound-minutes (0.90 kilogram-minutes).
 S 796-053
 (6)  
Slowly decrease the pressure to the ambient pressure.

 S 486-021

 (7)  
Remove the cap assemblies and the seals from the secondary heat exchanger.

 S 486-059

 (8)  
Install a cap assembly and a seal on each duct opening of the primary heat exchanger.

 NOTE: The test equipment must stay connected to the cap assemblies.
____
 S 796-022
 (9)  
Slowly apply 32.0 - 34.0 psig (221 - 234 kPa gage) pressure to the primary heat exchanger.

 S 796-060

 (10)
 Make sure there are no leaks around the cap assemblies.

 S 796-054

 (11)
 For 2 minutes, make sure the flowmeter does not read more than

 3.0 pound-minutes (1.36 kilogram-minutes).
 S 796-055
 (12) Slowly decrease the pressure to the ambient pressure.
 H. Do the Leak Check (Pressure Decay Procedure)
 S 796-035
 (1)  Slowly apply 30 psig (207 kPa gage) pressure to the secondary heat exchanger.
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 (2)  S 796-061Make sure there are no leaks around the cap assemblies.
 (3)  S 796-036Slowly increase the pressure to 64.0 - 66.0 psig (442 - 455 kPa gage).
 (4)  S 796-072Make sure there are no leaks around the cap assemblies.
 (5)  S 796-073Close the air supply valve.
 (6)  S 976-037Make a record of how much time is necessary for the pressure to decrease from 59.0 - 61.0 psig to 48.0 - 50.0 psig (407 - 420 kPa gage to 331 - 344 kPa gage).
 (7)  S 796-066Make sure the time is greater than 2.5 seconds.
 (8)  S 796-057Decrease the pressure to the ambient pressure.
 (9)  S 796-083Open the air supply valve.
 S 086-084

 WARNING: MAKE SURE THE AIR SUPPLY VALVE IS OPEN BEFORE YOU REMOVE THE
_______ CAP ASSEMBLIES FROM THE HEAT EXCHANGER. THE HEAT EXCHANGER IS PRESSURIZED UNTIL THE AIR SUPPLY VALVE IS OPENED. YOU CAN BE INJURED IF YOU REMOVE THE CAP ASSEMBLIES WHEN THE HEAT EXCHANGER IS PRESSURIZED.
 (10)
 Remove the cap assemblies and the seals from the secondary heat exchanger.

 S 486-040

 (11)
 Install a cap assembly and a seal on each duct opening of the primary heat exchanger.

 NOTE: The test equipment must stay connected to the cap assemblies.
____
 S 796-041
 (12) Slowly increase the pressure to 39.0 - 41.0 psig (269 - 282 kPa).
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