The PD does exactly the same as the WFCO wrt that four hours.
The PD without being Charge Wizarded will go into boost on a low battery. How low and what triggers that I don't know, but it won't if it is facing high R from a small battery bank or long thin wire or both. there is no four hours with that. It just gets the batts up to about 97% SOC and goes to 13.6.
If it did not go into boost then you can hit the CW boost button and get your 14.4 (or 14.8 on the ones with that) Now it will stay at 14.4 on the timer for four hours, while the battery does bulk and absorption. If the absorption stage gets down to 97%ish SOC before the four hours is up, the PD will drop to 13.6 "early" If the battery is not to 97% SOC yet, it will stay in boost until the four hour timer drops it to 13.6.
If the latter, you must hit the CW boost button again to continue the absorption stage until it does get to 97% SOC and drops to 13.6 to finish the recharge to 100% some day.
However, your Iota without its IQ4 will not do any boost ever. It is a single stage 13.6. With the IQ4 is is now a three stage but you cannot trigger boost with it once the converter drops from 14.8 to 14.2 It does what it does. It can be just fine as a charging profile depending on what you need for a charging profile. Or not.
The original PowerMax was a WFCO clone under licence, so it had that same 13.2 trigger for going into boost or not. PowerMax got away from that real quick and set their own design with its own profile. You get boost every time same as an Iota for 15 minutes regardless of the battery SOC. But, same as the Iota, if the battery was low to start with, it stays in boost longer until Vabs is reached. It then drops to 13.6 instead of the Iota 14.2. That will make it take longer to do the absorption stage at 13.6 instead of 14.2, but both those voltages are too low for fast charging off a generator ideally.
So for that reason, after much arm-twisting, PowerMax came out with their adjustable voltage model so you can control it all to suit any charging profile you want. They believe they have done folks that want that a huge favour--and they have! :) Meanwhile the vast majority of their customers are quite happy with the standard charge profile of the standard three stage models, just as most RVers only ever want their converter at 13.6 for when on shore power all their camping time so they don't care about any of this battery stuff :)
