Z2 increases pressure on leak; ResMed 11 doesn't

[SkySleep]

I've had my ResMed for only a short time and it's working just fine. Last night I tried a Z2 Auto for the first time. Both machines are set for APAP 4-20. Same ResMed P30i (pillow) for both.

The Z2 woke me up with very high pressure, so high that if I opened my mouth for even a few seconds it immediately dried out and I had to drink water. The air noise was also very disturbing. The ResMed 11 didn't do that.

Testing both machines today, with the ResMed 11 if I loosen one of the pillows or open my mouth, the pressure stays at 4. With the Z2, if I loosen a pillow or open my mouth, the pressure starts increasing. I stopped the test at 7 and it was still going up.

It seems that the ResMed 11 distinguishes an apnea event from a leak, but the Z2 isn't that smart.

Can someone with a Z2 and also something like a ResMed 11 confirm this difference: That the ResMed 11 (or whatever) doesn't increase the pressure with a pillow leak or an open mouth, but the Z2 does?

(It's possible that the Z2 would work more reasonably when set to CPAP, but I don't want to go that way. I like the APAP operation of the ResMed 11 and want to stay with that.)

I have a 30-day trial for the Z2 and am thinking of sending it back because of this behavior.

[SarcasticDave94]

Of the 2 machines, ResMed will be notably better. Why the difference in response to leaks, can't be sure without data. If you're still relying on default 4-20 pressure, it can be made much better.

[SkySleep]

... it can be made much better.

Not sure what "it" refers to? My ResMed 11? OSCAR reports pressures no higher than about 7. Perhaps you can help me understand what the range means. I'm thinking that if the pressure gets no higher than 7, it doesn't matter what the high end of the range is.

There is no data to feed into OSCAR for the Z2.

It might be possible to lower the range of the Z2 to 7 or so, but I see two problems with this: (1) at 7 over a long stretch (not just intermittent), the noise is still high and my mouth gets dry, and (2) it's certainly possible that from time-to-time I might need something greater than 7.

Anyway, I'm not trying to get around limitations of the Z2 or optimize my ResMed 11 (at this time, anyway), I'm trying to get confirmation that the Z2 increases the pressure when it detects a leak or an open mouth.

Thanks for your help...

[SarcasticDave94]

1. The ResMed will be better for therapy
2. It can be made better, it equals therapy on the ResMed, if you see data on OSCAR and fine tune it for your personal needs; as in "If you're still relying on default 4-20 pressure, it can be made much better". This "it" equals therapy

Another thread of yours indicates you seemingly do not want to tune it beyond default, but rather let it go as is. So there's no way it'll be better, as I was referring to checking stats and editing from default.

It is your therapy and therefore your choice.

But back to basics, ResMed over Z2 even if you travel.

[SkySleep]

1. The ResMed will be better for therapy
2. It can be made better, it equals therapy on the ResMed, if you see data on OSCAR and fine tune it for your personal needs; as in "If you're still relying on default 4-20 pressure, it can be made much better". This "it" equals therapy

Another thread of yours indicates you seemingly do not want to tune it beyond default, but rather let it go as is. So there's no way it'll be better, as I was referring to checking stats and editing from default.

It is your therapy and therefore your choice.

But back to basics, ResMed over Z2 even if you travel.

Thanks, but I'm still looking for a Z2 user who can confirm this increased-pressure-on-leak behavior.

[SkySleep]

UPDATE from the OP: I just now tried the Z2 with an ResMed F20 full-face mask (I had been using a P30i pillow), and was it noisy! I'm very hard of hearing, but even I was disturbed. I called over my sleeping partner, who has very acute hearing, and there's no way she would be able to sleep. (Muffler and the HME were installed.) The noise is from the connection to the mask, not in the area of the machine itself. The same mask on the 11 makes no noise at all. Both still at 4cm. (The noise is from the air flow, not the pressure. Two different machines can have very different amounts of air flow for a given pressure. That's possibly the case here.)

I was very cautious about the Z2, so ordered it from a retailer who has a 30-day trial.

The Z2 was to be my backup when traveling. The ResMed 11 would still go. I'm just going to get a second, refurbished 11 from the Supplier List here. That way I'll know that it will work for me.

[Deborah K.]

We could better help you if you would download Oscar and post charts.  Even without that, your beginning pressure is too low for most any adult.  This low pressure is intended for children and extremely small adults.  Your therapy and comfort would improve by raising your starting pressure to 7.

[SkySleep]

We could better help you if you would download Oscar and post charts.  

The Z2 provides no OSCAR data.