Oxygen Plumbing

[fluffysheap]

I have a 231 with the factory oxygen system. I can't figure out how to use it.

There are oxygen ports in the armrests, one for the pilot, and three in the back seat, with the little doors covering them. Opening the door exposes what looks like a 1/4" hole.

The plane came with a pendant cannula, and I have a supply of medical cannulas. These are all designed to have a plug inserted into them, or to attach to a barbed nozzle.

I am not sure what I am supposed to do to connect the cannula to the oxygen port. I have plugs designed to connect lengths of medical oxygen tubing together, but I am not sure if just sticking one of them into the port would be right. I suspect it would not be right.

The POH says nothing on the subject and I couldn't find anything on Google, either. Everyone seems to just assume you know how to do this, but I'm finding it entirely not obvious.

[Awful_Charlie]

I don't know what you have in a 231, but on the basis it is similar to a Bravo, you can find most of the technical details from the Avox website: http://www.avoxsys.com/products/  The adapters used to plug into the outlet ports are Scott type fittings, and are available with different restrictors in them, in the Bravo POH it specifies to use the ones with the Green band (which are the highest flow IIRC).

To use, wear the cannula/mask, plug the fitting into the hole and twist to lock it, and then turn on the main supply control knob.  If you have adjustable flow rates in the supply tube, adjust using the individual flow meters for each person.  If you have the altitude compensating regulator, it will do a fair job even with flow meters wound down, but of course YMMV and in any case, you need to keep an eye on it.

Also invest in an Oximeter to measure your saturation - and to be sure your system didn't get filled with compressed air!

Ben

[jwilkins]

If your system is similar to my 1980 M20K:

1. Have your OX tank checked to make sure it is there (some have been removed by owners who didn't use them), it is up to date on the hydro test so it CAN be filled, and doesn't leak. 

2. If everything is OK, seriously consider getting the OX Saver Cannula kit ( such as http://www.pilotshop.com/retrofit-kit-with-scott-type-fitting-p-2773.html ) Although they seem expensive, having the OX Saver and the adjustable valve will pay back pretty quickly. The fixed flow with regular cannulas blow trhough a tank fast.