invacare platinum 5, will this work with my Nortel minor burner? Help

Hello, I just got an invacare platinum 5 o2 concentrator, low hours and new filters. This is a little weak to run my Nortel minor burner. I have been working with an o2 tank forever with soft glass.
Any tips or tricks to get more pressure? Not sure of the lpm, but I need more. I am quite handy and not afraid to take this thing apart if I have to:bangHead:

keep buying more of them and hook them together. You not going to get any big performance improvement by opening it up.