Does Air Pressure Change using an add-on humidifier?

I ran out of distilled water last night, so I tried using tap water but gave a burning smell. I decided not to use my add-on humidifier and notice an immediate change in the air pressure without it. I have had the Cpap machine for about 6 weeks now and this was the first time, I didn't use the humidifier. I examined the humidifier: no water chamber cracks, no leaks, lid shut tight, hose secure on. I doubt anything is wrong with the humidifier, it's basically brand new. Do you get less air pressure when you use humidifier (at least that's what it feels like to me)? Any advice/suggestions are helpful, Thank You.

sallyvw wrote:Do you get less air pressure when you use humidifier...

Basically, no.

Would you please post details on the CPAP equipment you are using, in case there is something that might (or might not) be specifically related to it.

Cheers,

Bill