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coolfry73's Achievements


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  1. Ok, so here is what we got. 65 model acft (E model moded to HC-130P). Ok, crew has repeatedly reported acft will not pressurize to maintain 5K alt @ 20K agl (please don't just respond the acft can't pressurize to this std because our second plane here is doing great same model). When we check out system here is what we get. With GTC we can only get 7 in HG (our normal std is approx 8.5 in HG to meet std). HOwever, the cargo compartment (because we pressurize in full hot) just will not get hot and the flow is almost nill in both hot and cold. I have pressurized many planes and it should be very hot there and know you should be able to feel the air moving. Here is what we have checked and changed. Have R2'd two CC flow control and SOV and valve, reads approx half to a little more open in full hot with GTC. Have leak checked CC and FD heat exchangers. Checked visually the butterflies on both aux vent valves with cabin pressurized and there is no leakage. Have visually checked safety and outflow valve butterflies and they are full closed with no leakage. Have R2'd a CC turbine. Found the H2O separator exit duct cracked so R2'd that duct. Have leak checked cabin and found some normal leaks but nothing that is crazy. This check fails in pressurization manual mode with the GTC pushing about 40PSI and once under pressure drops to about 35PSI on the gauge. I have physically checked the underfloor heat SOV and it is closed but opens when demanded. Also checked the diverter valve to make sure it was operating, and it is. Also checked temp control valve butterfly operation and no binding there either. Checked ducting all the way up RH side of acft into cabin, no leakage. Pulled duct and inspected mixing chamber and flapper valve and saw no binding either. I just can not figure out why there is so low flow, it won't get hot in the cargo, and then we can't get pressurization to meet. I believe that pressurization is either causing the low flow (and I can't isolate it) or the low flow is causing the pressurization malf. Please throw me any thoughts on this subject. Thanks
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