Changing Pressure on Older Machine: Without a manometer?

I have the directions for changing the pressure on my Sullivan v elite, but they supposedly require a manometer. What does the manometer do? And can I do it effectively without the manometer? This is my thinking: You basically push down on a couple of buttons to increase the pressure and use the manometer for something, I guess to measure how much you're increasing it. But I was thinking that my machine has a light up guage that shows approximately what the pressure is, meaning there are no numbers, but you can tell by how far the light extends on the guage. So couldn't I do it using the light guage? Or not?

Similarly, I got the directions from an archived post on another sleep forum, but the writer said there was no guarantee you could change the settings back once you increased them. (An ebay dme guy also sent me the directions this morning without my asking because i had a question whether they were right for my machine, which is a whole other dilemma, because i didn't pay for them, nor did i say that i would buy them, so i'm not sure whether i should pay now that i have them.) Again, I realize it wouldn't be perfect, but couldn't you use the light guage as your guide?

Now, since this machine is supposedly a self-adjusting cpap, meaning that it delivers only the amount of pressure needed up to my prescribed maximum, which is 8, couldn't i turn this machine into essentially an autopap by changing the pressure to 20, and letting it deliver as much pressure as it wants? Or if I want that effect, would it be better to set it at, say 14, if i feel like 8 is not enough pressure now that i've been doing cpap every nite for the last three months?

Basically, my resistance to getting a manometer is that i would have to buy it on ebay, and they are not cheap, since i do not have a dme and don't know whether a dme would lend me one even if i had a dme with whom i have a relationship. i have insurance, but i guess i just dread the whole process of dealing with one, especially since i don't know whether i will get what i want (an autopap) and it may be a waiting process anyway, and i have pre-cpap symptoms--i'm tired.

Can anyone please help? Thanks so much.

Caroline

Caroline,

Look under "misc" on https://www.cpap.com They show 3 manometers. I have the Fisher and Paykel for 49 dollars and it does a great job. I tried to buy the 39 dollar one but they were out of stock at the time. It came with the humidifier tank however it works fine in the Remstar Autos humidifer. I think it comes as a set even though it would be nice if they sold it without the tank...Simply put the "zero" mark at the water line in the tank and turn your machine on. The water will rise and you read the markings on the tube...very easy!!

Later,

Marc

_________________

CPAPopedia Keywords Contained In This Post (Click For Definition): humidifier, fisher and paykel

Caroline,

I know that I have seen some posts on this forum on how to build your own manometer. All you need is a short piece of tubing and a ruler marked in cm's. If you can't find it on here, PM me and I will get some good instructions to you.

You can also get them on cpap.com. Look here
https://www.cpap.com/simple-find-cpap-products/misc
5th, 6th, and 7th items down.

Guys:

other questions: You put the manometer in the water? With a full tank of water? Even if my machine only uses a separate humidifier? So if I use the F&P HC150, I put the manometer tube in the water? And the pressure is measured in terms of cm's of water? I think I'm confused.

How about this idea of setting it on 20 and letting the machine do what it wants, essentially functioning as an apap? Will that work? Or should I do something more limiting, like 12, when my not-good-enough pressure is 8?

You can tell I don't know about this stuff. I'll check out both the cpap.com manometers and the build-your-own.

Thanks again.

Caroline

that was me again, with log-in problems.

caroline

Caroline,

Can you tell me what 2 buttons you press & how you do the sequence.

Please PM me if you want.

I have what looks like a V or an early VI machine (It is called a Resmed CPAP B) .

It too requires a manometer. Re these, you can very easily make one - I haven't checked all the other replies but bet someone has already provided a link to how to build a home made mannometer.

I have a guage & a pocket manometer. The little one cost about $15.

PM me if you want to know from where I bought it (out of respect for this being a cpap.com site).

DSM

dsm--

no offense, but what's the problem with plugging sullivan v elite into the internet or doing the ebay search i did?

at this point, i'm reluctant to pass along the results of my "gift" from the ebay dme, since i'm not sure what i want to do about it. i'm more conflicted than i should be about it, and i may make that a subject of another thread to get others' input. once i feel more settled about it, i may feel differently.

thanks for the info about the pocket manometer.

Caroline

Caroline,

Thanks for your feedback. I searched the net extensively - posted here several times - did every search I could think of - I rarely ask for help as I don't often need it. Your reply reminded me why

As I mentioned I have a Resmed CPAP B - it *looks* like a Sullivan.

But Thanks for your reply.

DSM

DSM:

Please pm me your email address. i am not feeling conflicted today. No ethical dilemmas at all.

Caroline

Caroline,

Many thanks - PM sent

DSM

The pressure of the machine is in centimeters of H2O. Essentially, a full atmosphere of pressure would raise a column of water about 34 feet. Now, you can work out the pressure in "PSI" by knowing that an atmosphere of pressure is about 15 PSI, and the ratio of 10 CM, say, to 34 feet, the cm of h2o is about 0.0142 psi.

My prescription of "11" could also be expressed as 0.1564 psi.

The point is that the pressure is almost tiny, and the unit of Centimeters of Water is a convenient unit - people work better in convenient units.

But the flip side of this is that gauges that can measure these tiny pressures are both expensive and delicate. The good news is that a plastic tube can be dipped into the water with the pressurized air above it, the zero mark can be aligned with the surface - and the plastic tube is actually more accurate than the fancy, expensive mechanical gauge.

At least one DME I knew of would check and recalibrate their mechanical gauges every morning to their water column manometer, and if there was a significant difference, would send the route man back out to redo the sets that they did the previous day, or so they claimed.

Now, as pointed out, the new machines have their own built in gauges - but I have checked one older CPAP and found that the indicated pressure differed fom the water manometer by 1.5 cm water at a pressure of 10 cm. Not a big sample.

Personally, I would not trust an older machine to be accurate and I would not believe that I could reset something without a manometer.

brasshopper and dsm and all:

i have a tire guage, not the skinny kind, but the one that's about two inches wide in a circle that you use for trucks. so would i be better off making my own or buying a pocket one or buying one from cpap.com.?

my machine is not that old; it's five years old, which feels archaic next to some of those you all have.

it's also, as i think i have mentioned, a self-adjusting cpap that adjusts up to the maximum pressure set. but unlike an autopap, the prescribed pressure is the top level set. i'm not sure that i see the difference between that and setting it differently so that it works like an autopap, meaning intentionally set it too high so that it will just find its own level during the nite.

thanks for all your help.

caroline

High points: A tire pressure gauge measures 100 PSI. A gauge to check the pressure on a CPAP would measure 100ths of a PSI.

You can easily make your own manometer from a U shaped plastic tube - the ones sold by cpap.com solve a lot of the problems for you - how to hook the manometer up and allowing it to "bleed" a little. You use the supplied water container for convenience. No reason I can see that you should not be able to just stick the "bleed cork" into your own humidifier, and zero the sliding tube with the water surface and then read the pressure.

Few of the manometers on eBay are suitable for your needs. Item 7622832488 migt be - but you still need to attach it to something to hold it and to attach it to the CPAP. It should have enough accuracy and twenty inches is plenty of range, you need 20 cm. Many of the manometers just read too high of a pressure, or with not enough accuracy. This one, item 7623020882, probably would be accurate enough but it reads to three inches only - which is only 7.62 centimeters - not enough for your or my cpap needs - it was likely used for Scuba regulator setting - where you want the cracking pressure of the primary to be light and you test them with a manometer like this and a flow bench. You need a manometer that reads to at least .25 cm accuracy over a range of about 5 cm to 18 or 20 cm. Hard to tell that from those descriptions.

I just don't know anything about your machine so I can't comment. I don't know if the machine tries to stay at the top end and uses the "automatic" setting like a long ramp. So I can't comment on the advisability about settig your pressure up to 20 CM.

There was a canadian study that said that people could set their own CPAP pressures based on how they felt pretty accurately - but they had some training and stuff that you can't get here so it is not right to say that anyone can set their own pressure without training. We can't apply the study to the world in general without the training.

I do know that were it me, I would make small, slow changes - I would not set the pressure to 20, I would change by 1 cm maybe and see how I felt.

As far as archaic goes, I used the same CPAP machine for 18 years and just swapped it out last week - what I learned here taught me a lot about what to ask for and why and I think that my long term therapy will be a lot better off because of it.

brasshopper:

thanks. i wasn't really considering the manometers on ebay after den and others said there were cheaper on ebay.com, and as a result of your research, much better suited for cpap anyway. i hope you didn't go to too much trouble checking out the ones on ebay for me. thanks also for letting me know that my tire guage won't work. i just have to dig out the posts on making your own, seeing if that's do-able for someone like me who is not too mechanically savvy, or if it's just easier to order a $39-49 one from cpap.com.

as for archaic, i have to get off my rear end, find my old sleep study, and go to my doctor (who has no idea i have apnea--he hardly knows me) and go through the channels to get an autopap. i dunno what insurance will say. so far, i just asked an insurance rep who said if they covered my machine under my old policy, they would cover it under the new policy, even though the new one is an hmo and the old one was full-fledged, in-network, out-of-network individual insurance. she said they had no set time period for replacing machines, but she seemed to think that five years of ownership was a reasonable time period to be now asking for replacement. she said i could just ask my regular doctor to write a prescription for a new machine. course, she's not the one making the decision, and she doesn't know cpap from autopap. i'm envisioning a hassle but maybe it won't be.

thanks again.

caroline