houdini
How big a room you trying to fill? also what gen you getting I would get the cap either gen 1 or 2 (get the E model its piolotless ignition)depending on your room size they are expandable the gen 1 does up to 12 cu ft co2 an hour the gen 2 does up to 24. thats with all the burners each burner is 3 cu ft a hour the more burners the less time it is on. my 5 x 8 room takes about 2 minutes to fill to 1000 ppm every 20 min. a 5 gal propane lasts about 2 weeks. compared with a 20lb bottle of co2 every 4-5 so the savings are good. allthough in the summer I have to switch to bottles sometimes. we had a 109 degree hot spell that lasted about 2 weeks my temps got up to 92 so I cut the gen and solved the problem but 2 weeks out of the year isn't bad. Also you mentioned something about priming the pump I have heard the term before maybe you can enlighten me. I was thinking maybe the siphon break in the line some how messed with it but I had those before with no problem.