Truckerdad pretty well points out that the humidifier is substantially a trial and error settings issue, learning by OJT (on the job experience
I discovered yesterday for example, that the blasts of cold air were because the humidifier had quit operating. (Um duh on me). I took it in to the local DME sole supplier whose abysmal technical support said the plate is heating up So, everything is fine. I asked about control setups having inadvertantly been turned to 'Off'' and was brushed off.
So, the point is you need to be proactive and self advocating when you have questions. I later groped around the user-accessible panel settings and found the soft setting to turn it back on.