[Equipment] ResMed Quiet Air Diffuser Vent F30

[Sleepster]

Instead of my CO2 exhale going out the pinholes as intended because of the pinhole and right angle and fabric packing extremely restricted passage, the CO2 rich exhale is just taking the path of lesser resistance and mostly being inhaled back up the elbow into my lungs along with the fresh air that’s being pumped by the CPAP unit.

I can't tell if you're talking about a modification that you made, or if you're talking about the unmodified product furnished by the manufacturer. If the latter, then you are safe.

The purpose of exhalation port is to keep the tubing purged of exhaled air thereby insuring that there is always a fresh supply of air being delivered to the mask from the tubing. The amount of exhaled air that remains in the mask to get inhaled again is negligible.

[Big Guy]

I just realized that I haven't updated my posts. I received my F30 mask assembly several months ago. It's now my go-to mask. I use it most of the time, but occasionally switch to my F20 AirFit just for a change. 

That usually only lasts a night or two..............

[Vamurphys]

I’ve come to the conclusion that I would rather have better airflow, and less rebreathing of my CO2, then “quiet”. Removed all the packing from the elbow and seem to be sleeping better with the less resistance of the packing in the elbow.

[DaveL]

Interesting conversation. I was given an F20 to take home for a week's trial. It didn't work out for me. Leakage was severe on my face and I took it back.

It was the most comfortable full face mask I've tried.

I never tried the other insert in this mask to see if I could wear the mask all night, with less leakage.

[car54]

This topic is of interest to me because I have used both vents. I also have impaired lungs, asthma, COPD ,allergies. emphysema and bronchitis. I have lost 40% of my lung capacity. 

I tested the flow of each by blocking the holes except the air vent and measured that  time a gallon of water needed to be emptied. Here are the pictures.




They old vent took 1 minute and 4 seconds and the new one was 1 minute and 2 seconds. Draw your own conclusion. To do a proper test I would check the air flow rate at a specific pressure and I don't have the equipment to do that.

car 54

[SarcasticDave94]

Well that is telling.

[RayBee]

Brilliant car54.
Thank you.

[elliotg]

I am afraid that this issue is still current.  I have both the quiet and  original version of this mask elbow.  After testing both, I could find no difference in their functionality apart from the fact that the quiet mask did not blow an airstream at my wife. So I settled on that one and have used it for close to 9 months.  But a week ago or so, I was finding that whenever I reached my high pressure (13) the mask was leaking badly and no amount of strap tightening would stop this. The mask was literally being blown off my face. I then remembered this discussion and guessed that the exhaust path was being partially blocked and causing back pressure.  So I changed to  the original elbow and the problem vanished.

When I took the elbow apart the back spots which others have mentioned were very apparent.  So it is clear to me that the venting was indeed restricted in the quiet elbow but only became so after a considerable time. I would still want to use this type of elbow and have ordered a replacement - they are not that expensive.  But I was unable to find information on the Resmed site about the need to replace this part after a period of use.  Or how to clean it.  I have seen various suggestion on this board, but I am not sure which actually work well.  I find cleaning something that you cannot see (the diffusor material ) a rather unsatisfactory task. Or perhaps I should just be prepared to get a replacement every 6-9 months?

[RayBee]

eelliotg, if you want to continue to use the ResMed Quiet Air Connector PN 63494 with the internal diffuser material, just soak it in 100% distilled vinegar for a while, rinse in clean water, let air-dry, and reuse.

"a while" is subjective. I've soaked mine in a small cup for up to two weeks to see if the discoloration would go away. It wouldn't. But the "gunk" does seem to get thick over months of use without the vinegar treatment. It seems that the gunk goes away and original flow is restored, but the discoloration remains. I have several of these and swap them out accordingly as one needs the vinegar treatment.

I have replaced the diffuser material (posted somewhere earlier in this thread) and found that the little black dots appear on my home-brew diffuser too. Overall, kind of a PIA to do and IMO unnecessary if you just do the vinegar soak.

Personally, I would say try the vinegar soak for one or two days every one or two months. And have two available to keep in rotation. If you don't like to black dots, just keep a spare on hand and figure out when your Quiet Air elbow nears its end-of-life and discard it - consider it a consumable.

How to spot the spots... Use a jeweler's loupe. Look into the tiny holes while shining a strong light through the side of the translucent diffuser cover.

[elliotg]

Thanks RayBee. This all seems to be good advice!

Elliot.  

eelliotg, if you want to continue to use the ResMed Quiet Air Connector PN 63494 with the internal diffuser material, just soak it in 100% distilled vinegar for a while, rinse in clean water, let air-dry, and reuse.

"a while" is subjective. I've soaked mine in a small cup for up to two weeks to see if the discoloration would go away. It wouldn't. But the "gunk" does seem to get thick over months of use without the vinegar treatment. It seems that the gunk goes away and original flow is restored, but the discoloration remains. I have several of these and swap them out accordingly as one needs the vinegar treatment.

I have replaced the diffuser material (posted somewhere earlier in this thread) and found that the little black dots appear on my home-brew diffuser too. Overall, kind of a PIA to do and IMO unnecessary if you just do the vinegar soak.

Personally, I would say try the vinegar soak for one or two days every one or two months. And have two available to keep in rotation. If you don't like to black dots, just keep a spare on hand and figure out when your Quiet Air elbow nears its end-of-life and discard it - consider it a consumable.

How to spot the spots... Use a jeweler's loupe. Look into the tiny holes while shining a strong light through the side of the translucent diffuser cover.