Ask The Brewmasters

I have a CO2 recovery machine that is only rated at 4 PSI inlet pressure. My vigorous fermentations produce upwards to 5+ PSI. My question to the community is if I can regulate the input pressure to my CO2 reclaim machine to be 4 PSI or less and have the excess pressure stay in the fermenter as I capture that CO2. At what pressure in the tank would I possibly start effecting the actual fermentation or the health of the yeast? The bulk of the CO2 collection is done during high krausen as you can imagine.