A10 makes odd sound on startup

[PaulaO2]

The sound is similar if not identical to the rainout snore. Except there's no moisture in the hose. I've even started hooking the hose on the wall so both ends are pointing straight down. I also feed it through my hands to make the alleged water go down. Yet it still makes the noise. It is really loud, too. Just one pop, gurgle, snore, whatever then nothing.

A10 Autoset, Nuance mask, heated hose, using humidifier.

Could it be the humidifier?

[mesenteria]

Maybe an older seal in the humidifier lid that rattles a bit before settling?

A bit of water in the machine...highly, highly unlikely since it should dry within a few hours at most.  Although if the tub has a minute leak, perhaps whatever is seeping makes replacement more likely.

A worn shaft pillow-block or bearing that now has some play, and the shaft is displaced just enough with daily handling (replacement of the humidifier vessel after filling?) that, upon startup, it quickly spirals toward a detent and makes a sound when it does?

I'm swinging in the dark here....you'd better duck.

[Fats Drywaller]

You can find out whether it's the humidifier by removing the tank, disconnecting the air hose from the back, and plugging that into the air outlet that feeds the humidifier. Start the machine. If the noise still happens, then it's not the humidifier.

P.S.: Oh yeah, I forgot, heated hose. For testing, use a regular unheated hose with the rubber shroud connector.

[PaulaO2]

Every night, this machine made that noise. Then I ask on here, and it has not made it since. I should have asked sooner!

If/when it starts again, I'll do the "hose where the humidifier goes" thing.

[AlanE]

also give a quick glance to the inlet filter. If it is blocked or has started to fall apart a piece may be getting sucked part way into the inlet on startup.

[PaulaO2]

Ah! Good idea! I changed it after my visit up Nawth. And the sound did not occur before that. Hmmm. I'll let you know what I find.

[PaulaO2]

I recently got a new humidifier tub. And the noise is gone. There must have been something with the seal maybe?