Did the Boeing 727-100 havemore than 1 configuration A/C system?

Question

Specifically did any -100's use a 3 port mix valve (like the -200 did) as opposed to the 2 port valve on some configurations of -100

Answer 1

John I like your answer.

As a mechanic who's worked on a few 727s, I don't care unless I have to replace it.

Most of the work I did on the -100 was ripping **** out before they were scrapped.

http://www.airliners.net/photo/Untitled-...

Answer 2

I honestly don't know why as pilots, we try to complicate issues like we do. I guess it's so people will think we're something special. But of course we're not. That's the cockpit of an executive 727-100 you see me looking out of the window there in my avitar. The short answer to your question is no. And the long answer is nnnnnnnnnnnnnnoooooooooooo.

Answer 3

MIX VALVES

The amount of cooling produced by the pack is determined by the position of the mix valves. The hot and cold mix valves are linked together to one mix valve actuator. As one valve opens, the other

valves closed. When one is fully open, the other is fully closed. If the cabin needs more cold air, the cold mix valve is moved to a more open position and the hot mix valve moves toward closed. Less bleed air goes through the hot valve and more air is forced to go through the air cycle machine and cold mix valve. As more air is processed by the air cycle machine, it works harder, increasing its internal temperatures and pressures.

MIX VALVES 200/A

Each 200 air conditioning pack has three mix valves; hot, cold, and Intermediate, driven by one actuator. The intermediate valve, when open, permits the bleed air to be cooled by the primary and secondary heat exchangers without passing through the air cycle machine.

As the mix valve actuator moves from full hot towards cold, the intermediate valve and cold valve open as the hot valve closes. When the mix valve position indicator has moved approximately 60% of its travel towards cold, the hot valve is fully closed and the intermediate and cold valves are full open.

At this point all the bleed air passes directly

through the heat exchangers where it is cooled by ram air. The air doesn’t flow through the air cycle machine because the air cycle machine offers more resistance to the flow of air than the direct path through the heat exchangers.

So to answer your question the 727-100 and the 727-200 have slightly differing air mixing valve systems.