Oven spring in professional deck oven
I've just recently started doing some baking in a professional deck oven, its a mono oven 4 years old with a steam system. I was quite excited about baking in it, as I've only every really used my old domestic gas oven at home. My basic white sourdough (800g of dough, 75% hydration, 4 hours bulk ferment, 12+ hours cold prove in banetons), is something I get consisten results with when baking at home using the dutch oven. I always get good oven spring and great looking blooms.
So when I started doing it in the professional oven, I thought I'd be on to a good thing, but the results are really inconsisted. Infact, most of the loaves don't bloom at all, I get loaves with a failed slash that puffs up a bit but never forms a nice ear or rip. I've tried a few different temperaturses 260, 230 and 240 degrees C but results are always poor.
I thought that I'd get better results in the professional oven, with better heat transfer and the steam system but I can't seem to crack it. Any ideas as to what I'm doing wrong? Too much steam, too little steam, wrong heat? Any help would be greatly apprecieated.