Have you used the machine for five years, or did you get it recently but it was already five years old? How long have you been using CPAP?
This is before you have updated your profile, so I'm assuming (yeah, I know that's always hazardous) that you have a Resmed S9 since you say there's no wireless datacomm. If the machine is something else (an S8?), then skip this first part: You can download PDFs of the S9 user's guide and "quick start" (or welcome guide) here. These are the UK editions; I couldn't find the USA editions with a quick search.
S9 user's guide:
https://www.resmed.com/uk/dam/documents/...r1_eng.pdf
S9 welcome guide:
https://www.resmed.com/uk/dam/documents/...r1_eng.pdf
To get the more sophisticated instructions for changing your machine's settings (for any model of machine, not only the S9), use the "CPAP Setup Manuals" link at the top of the apneaboard web page and follow the instructions there to request the PDF by e-mail using your exact machine model name.
When you negotiate to get your replacement machine, it's best to ask for a "Resmed Airsense 10 Autoset for Her" because that's the best and most capable machine available. If the DME that you're dealing with can't provide that model (which is unlikely), it's OK to settle for the same thing without the "for Her" suffix; that one is almost as good. Those two have the same retail price, by the way. The most important point it that it should be an Airsense 10
Autoset; don't settle for an "Airsense 10 Elite" or "Airsense 10 CPAP" or anything else. The insurance HCPCS code for all CPAP and APAP machines is the same, E0601, and the reimbursement amount to the DME is the same, so the DME has no good reason to refuse you the specific machine that you ask for within that lowest tier. That's assuming that your sleep apnea is OSA (obstructive) and is treated effectively with CPAP/APAP and you don't need the more advanced bi-level or ASV. The Resmed series for those machines in the two higher tiers is called Aircurve 10 rather than Airsense 10, and those have different insurance codes, are more expensive, and require different prescriptions.
The "Machine Choices" wiki article that Wally pointed to is excellent, but all that information (in addition to the above) might be overkill at first, because at the end of the day (and the night) it really is as simple as saying "Airsense 10 Autoset", preferably with "for Her".
