Aussie Hose, Rainout and NV Mask

[Lubman]

I am having a rainout problem with my Aussie Hose -- which is a great product, perhaps due to my setup. I use an F&P humidifier set at about 2+
and external OX 3 ML feeding in at the humidifier input from the machine.

Just finished reading all the posts on this topic, thanks to RG's links and
will check polarity of the power connection - but otherwise need some tech analysis of what may be happening.

I received my hose in December with the 12V PS. Using 12V seemed to dry my mouth out considerably, so I bought a 9V 1.5A supply from Radio Shack.
Now Radio Shack has adapters for the plug connector and it is possible to plug in that connector two ways, if the hose really cares which side is +12 and which is common you have a 50 50 shot at getting it right.

I would opt for center pin at + and outer part as common or -

My mask is non vented and I have 12 inches of rebreathing tubing before encountering an in line vent -- which is not typical (and not recommended unless so prescribed), but I believe that the small amount of heat created
by the hose collects a bit more in a NV mask than in a standard vented mask.

At lower voltage, the mask was working and little or no rainout and minimal drymouth.

Now I'm getting rainout nightly, in a cooler room about 68 deg F and 20% humidity.

I talked to Don at Sleepzone -- he wasn't sure on this one.

It seems that the wet face from rainout is contributing to a leaking mask seal not to mention that it wakes me up.

Here's the approach as I see it

a) Test the hose to insure it is heating
b) If not, change DC plug polarity into hose
c) Not sure at this point if I should again reduce the humidifier settings
or do I conclude that using this with a non vented mask in a cooler room is a poor combination?

Any ideas?

Lubman

[Pilot_Ron]

what was the amp rating on the original supply? I have an Aussie hose at home, but I am at work. You have dropped the voltage by 25%, but the amp draw for the heater would be increased by that much. The heater will attempt to draw as much power as required based on its resistance. It will therefore try to pull more power than the output capable of the transformer. You may have cooked the transformer and not even realized it.

Also a possibility that the 1.5 A/ 9V is not enough to get the hose warm enough to exceed ambient temperature.


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CPAPopedia Keywords Contained In This Post (Click For Definition): hose, Power

[gandalf]

This is confusing to me as I would think if you were feeling "dry" you would increase the humidifier level thus increasing the humidity content.

The heated hose keeps the outter part of the hose warmed above the condensation point of the humid air passing through. Lowering the voltage to the hose lowers its ability to warm the hose, increasing the likelihood of condensation/rain out, which would decrease the humidity of the air.

So how does lowering the voltage on the hose make you feel less dryness?

[ozij]

I use the hose on a 12V power supply with a central pin at +. I had to add a snuggle hose cover to the heated hose, to avoid rainout. I also wrap the narrower tubes that connect to the main hose to the mask.


O.

[Lubman]

what was the amp rating on the original supply? I have an Aussie hose at home, but I am at work. You have dropped the voltage by 25%, but the amp draw for the heater would be increased by that much.[

The original 12 V supply was at 1 AMP. However, I think the hose will draw only the current it requires at whatever voltage is supplied. If the hose has about 13 ohms of resistance -- ohms law is quite simple it is Current = Voltage divided by resistance. So we are talking the difference between 12 /13 and 9/13

Many posts on this site indicate people find the 12V provides a bit too much of a change and that a lesser voltage adapter seems to be adequate. Agree that the lower voltage lessens the temperature ambient in the hose.

[Lubman]

I use the hose on a 12V power supply with a central pin at +. I had to add a snuggle hose cover to the heated hose, to avoid rainout. I also wrap the narrower tubes that connect to the main hose to the mask.


O.

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I verified that the central pin was + and raised the temperature in the room from 68 to 72. Last night no rainout. (day before the cord came detached at the adapter and believe it was reversed for at least one night) O., I think you are right, adding a snuggle hose over the heated hose will help.

Now how can i reliabily wrap the short rebreathing hose? It is adjacent to an inline vent that i can not block - that is my venting. If snugle hose was available in shorter parts and could be firmly secured to the short hose sections -- so that it could not slip over the whisper valve vent -- that would work. Will any rainout occur due to the non vented mask itself or does the condensation all come from the hose running through a cooler room? Because if any additional insulation / covering was needed for the actual mask that would be a bit of a mechanical challenge.

Lubman

Lubman

[ozij]

Reliably wrapping the short hose:

I use a few layers of tubular finger gauze. I put a plastic wrap on the one side of the hose to make slipping the gauze over it easier (and then pull it off, off course). If you're concerned about about the wrapping slipping on the vent, how about using micropore tape of something similar to tape the edge a safe distance away from the vent?

I'm sorry I can't help you with the "condensation in the mask" question - I've never used a nasal or FF with the heated hose, only nasal pillows masks.

O.

[TerryB]

The heater in the Ausie hose is a continuous piece of wire with a resistance of about 13 Ohms. It doesn't care whether the power supply is hooked up +, -, or even AC instead of DC. So don't obsess about that hookup.

Also, I'll bet that the NV mask is agravating the condensation of your own warm breath onto the cold mask. No matter the source of the humidity, when the humid air cools on a surface, condensation occurs. Remedies are decrease the humidity, increase the temperature.

Good Luck,
TerryB

[GumbyCT]

Lubman,
I for one am not really sure exactly what problem you are having. Perhaps you can give one sentence telling what the problem is.

I sleep in a room at 60 degrees so I am not sure 68 is going to give you troubles? I would say if rainout is your problem start with your machine on the floor.

As mentioned condensation of any moisture in the air will occur when it comes in contact with cooler temps. With the machine on the floor, any condensation you get should run back to the machine. Keep as much hose below the level of your head as you possibly can, let gravity work for you.

If I have any condensation, I am not aware of it because of this configuration. My dads evil dme recommends emptying the hose each day. I would just raise the hose so it runs back to the tank.

But you can certainly use this idea to check for any accumulation each day too.

If you want to wrap something just use your imagination for materials - an old scarf or towel strips secured w/tape, rubber bands, string, or velcro. Or even use an ace bandage or cling to wrap. Cut as required.

Good Luck,
GumbyCT

[ozij]

When water condenses on a part of the mask that is near your face, you can't really make it run back down to the humidifier....

And, rainout it a bigger problem for those of us whose pressure is lower.

O.

[Lubman]

how about using micropore tape of something similar to tape the edge a safe distance away from the vent?

I'm not familiar with micropore tape will ask the DME. This sounds like a good idea. The short section of tubing used for co2 is very flexible and tends to bend while in use - so anything attached would have to be very plyable.

Good idea.

Lubman

[Lubman]

When water condenses on a part of the mask that is near your face, you can't really make it run back down to the humidifier....

I think O. is correct. Terry asks why not place the machine on the floor.
That might help water from the hose to run down into the machine, but when one has a non vented mask and another flexible section of tubing on your face beyond the end of that hose, the source of the condensation may be in the mask - which is heated by the air in the heated hose and ones own breath on the inside and is exposed to cold air on the outside.

I still think there could be a difference in temperature inside the non vented mask, where if I had a vented mask, the temperature might differ slightly and the results could be different. Not sure.

All I know is I am waking up earlier and am tired. The mask with water
or dryness appear to be a factor.

Lubman

[Lubman]

Sorry, attributed quote to Terry that was from Gumby

[Hiitsmepam]

I was tired of the rainout...I have my machine with humidifier on a box next to the bed, below head level. I pull all the tubing under the covers with me. My body keeps the tubing warm and if there is an condensation, it goes back down the tubes into the tank. I've had no problems since then.

[GumbyCT]

...and if there is an condensation, it goes back down the tubes into the tank. I've had no problems since then.

Make gravity work for YOU. Don't fight it - go with the flow!!! Wish I thought of that!!