ZMOD4510 warmup and timing question

Hi, I've been running some test on the ZMOD4510 and O3 concentrations never went up from 0, so there's probably something I'm doing wrong...

Our application has to get O3 concentration every 20 mins. The implementation of the firmware is done in a way that performs the reading like it's suggested in the Programming Manual, (table 4), runs the first algorithm calculation, sleeps for 20 mins and starts from step 5 of the program flow (start measurement).

According to table 4, the 2s delay is needed between measurement and status register reading, but is there any timing needed between algorithm ending and starting a new calculation? Can the sensor perform the warmup routine without needing a read of the status register every 2s or so?

Thanks in advance.