H5I auto shut off when empty?

[Denial Dave]

2 weeks into therapy, I have a head cold

I went to bed early around 8:30PM last night, I filled the humidity tank and cranked the humidity up to 4.5

Around 4AM, I woke up and noticed a temperature change in my air supply. The air was warm, but not bothersome, so I went back to sleep!

my alarm clock rang at 4:45AM. when I removed the humidity tank, it was warm and completely empty.

My question is, if the humidity tank runs dry overnight, will the H5i keep trying to heat the tank or is there an auto-shut off safety feature?

I've searched the resmed site and can't find anything about an auto-shut off of the heat, when the tank is dry.



Dave

[Denial Dave]

I think I found the information I asked about in the Clinical Tech manual

Maximum Temp of the H5i is 150F / 65C

Temperature Cut off is 165F / 74C

So, if I understand the information correctly.

If your H5i is run with an empty / dry humidity tank; it heats to a max of 165F/74C, will then cool down until the overtemp sensor resets and then it will heat up again.

The H5i will repeat the above overheating / cooling cycle until you turn off the machine.

That is the extent of the overtemp safety for the heating coil on the unit.

Dave

[billbolton]

ISo, if I understand the information correctly.

IMO you haven't..... why don't you ask a specific question directly to Resmed

[ozze_dollar]

I have run mine completely dry so it does not turn off.

[StuUnderPressure]

The ResMed H5i Heated Humidifier does not turn off automatically when it runs out of water.

It does however have a "safety" feature that turns it off if it gets too hot (as the OP apparently found out himself).

But "my experience" has been that even running the humidifier without water for several hours does not reach that safety cutoff temperature.

[-tim]

So.. no, no it doesn't.

It has no idea that there is no more water and just keeps running the heater.

They could have put a capacity sensor on it (just like the touch on/touch off lights) but that may be covered by a patent or prior art (if no prior art, this post shows the concept is non-patentable)

[Denial Dave]

I e-mailed an inquiry to RESMED about it and when I get a response, I'll post it

Dave

[Maholly]

I was awakened by a strange smell in my mask in the middle of the night. I discovered that the water tank was dry and that the tank was very hot. Further, the heating plate was too hot to touch. I do not see how it is possible to use the humidifier.

[ozze_dollar]

I was awakened by a strange smell in my mask in the middle of the night. I discovered that the water tank was dry and that the tank was very hot. Further, the heating plate was too hot to touch. I do not see how it is possible to use the humidifier.

Wow,what temp do you have it set at?

[Johnny APAP]

Even if mine has a bit of water in it, it's making a loud steaming noise in the middle of the night and then turning itself off. It keeps doing this every few minutes. It's incredibly annoying. I have to either turn off the humidifier or refill the tank. It doesn't seem to make it more than 6 hours. Has anyone else experienced this? Is it a defect?

[mrsbongo1]

Check your hose. If the machine is turning on and off it could be the hose. I got this info from ResMed tech support, which I blew off, replace the H51, when it happened again I check the hose, sure enough the hose must of had a small defect, replaced it, been going great for the last 6 months, even the few times I've run in dry. Hope it helps. Kathy

[Johnny APAP]

Thanks,

I'll check the hose. To be clear, the machine is making a loud hissing sound that lasts only 5-10 seconds and
it starts about 6 hours into my sleep. The airflow part of the machine is working properly through all of this
and doesn't deviate in pressure. So, I wonder where the hissing sound is coming from. I suspect the humidifier
and I wonder if it can somehow do an "emergency" vent. It only seems to be "happy" and stop making this sound
every few minutes if I add water, but the reservoir has never been completely empty or even
below the min line. Refilling the tank seems to stop the problem, but I'm tired of being woken up
to this 6 hours into my sleep. I twiddled the humidifier settings and it still continued. After reading this thread,
I'm being very careful now to ensure that I don't have any mask leakage and its stopped for the moment - but that
could also be because the weather has warmed up and the ambient humidity is higher. I don't really understand where the loud hissing sound is coming from. As I said, it's not from a change in the pressure the machine is putting out.
I'd appreciate any ideas.

Thanks MUCH,

John

[chunkyfrog]

The continued heating is enough to roast any biofilm which remains once the water is gone.
The smell wakes me up--the tank doesn't even have to be completely dry yet, especially if it's been few days since I washed it.
The scent is not intense--just unpleasantly funky.
I always check my hygrometer for the room humidity, so I have a good idea how much water to add.
I'm getting better--only ran dry maybe once this winter.

[Slartybartfast]

Your profile doesn't state whether you have the heated hose, too. I do. When my H5i runs dry I notice the air gets warm and then suddenly the machine shuts off which awakens me immediately, and I see an error message in the window, to the effect : "Replace heated hose." Perhaps with the heated hose, temperature rises above a certain point, triggering a shutdown and error message. If you don't have the heated hose your mileage might vary, as they say.

[StuUnderPressure]

Your profile doesn't state whether you have the heated hose, too. I do. When my H5i runs dry I notice the air gets warm and then suddenly the machine shuts off which awakens me immediately, and I see an error message in the window, to the effect : "Replace heated hose." Perhaps with the heated hose, temperature rises above a certain point, triggering a shutdown and error message. If you don't have the heated hose your mileage might vary, as they say.

You must have an S9 with an early version of the internal software.

The newer versions of the internal software no longer give out that error message.
The humidifier is just shut down if it reaches a certain temperature (whether it is out of water or even still has water).

DMEs & ResMed replaced a lot of heated hoses & even a lot of Humidifiers before they realized that nothing was wrong with either one. Basically, they just removed the error message. The protection of the automatic shutoff when a certain temperature is reached is all that is needed anyway.

Don't know if this fits your particular environment, but those who were getting that error message kept their bedroom temperature rather high and / or the heated hose was set at a high temperature AND was run under the blankets or otherwise covered. Actually, usually both things were occurring at the same time.