AC Pump Trips Main Breaker

Is it common to feed multiple a/c units with a single pump vs a pump for each unit? I have two chiller units for my a/c but each one has a pump feeding the raw water to the respective unit. I get that this adds inlets/outlets and hoses but with one pump only, seems like you lose everything when that pump fails? Is there a benefit of a single pump other than just to reduce plumbing?

In terms of redundancy, it's actually the other way round: in your setup, if one pump fail, you lose whatever half of the boat that chiller unit is serving.
As opposed to that, if the system is designed with just one large, multi-compressor chiller (and I've seen up to 4 compressor in a single unit, rated for 300k BTU), by definition there's just one inlet/outlet, BUT it's normally installed with at least two switchable and fully redundant raw water pumps.
In turn, this means that if you lose one of them, you lose nothing, anywhere onboard.

Um no, sorry you are mistaken. I have dual chillers feeding a single chilled pipe loop throughout the boat with all air handlers off the single chiller loop. One chiller can handle the loop by itself but best with two running. So each pump/chiller is redundant to the other.

Aha, I see.
I assumed that the only reason for two separate chillers was to place them in different parts of the boats, each connected to its own loop.
If they are placed together and connected to a single loop, I honestly struggle to see the point, when one chiller with two compressors would be simpler and equally redundant (if installed as I previously said).
Was your installation possibly meant to be able to run just one chiller if and when dock power is limited?

Same here. I have two fives in sequence. One is set to fire at 54 and shut down at 46. The second is set to fire at 57 and shut down at 49. I think if I had it to do again I might have split the first into a two follow day a three along with the second five. The wear would be on the two as so many cycles run just to cool the loop, and the sacrificial unit would therefore be a smaller size and cost. The regular power draw would be somewhat less as well on average.

True, in principle. But in practice, I never heard of anything but a compressor failing, in a chiller unit.
And one faulty compressor has precisely the same consequences if installed in one of two single compressor chillers, or if it's in a single twin compressors chiller.

The series setup shares a glycol loop pump for the chiller loop. They share a raw water cooling pump that feeds multiple coils. But everything else is unique to the individual chiller.

Guys, I fully understand the principle.
But a twin compressors chiller works exactly in the same way as two single compressor chillers, for any given total capacity.
The Condaria system in my boat has a single chiller with two compressors, but they very rarely run together, aside from when the systen is started and the coolant in the loop is rather warm.
In this condition, with both compressors running, the whole loop is cooled faster.
But once the preset temperature is reached, both compressors cycle on and off automatically, and almost never run in parallel anymore.
Besides, as I said, I've seen single chillers with 4 compressors and a total capacity of 300 thousands BTUs, which is superyacht territory.

The point which Pascal raised is that two completely separate chillers are better for redundancy compared to twin compressors single chillers, and I did say literally that it's "true, in princple".
Where our experiences differ is that I never heard of any faults with these Condaria multi-compressor chillers, aside from the odd compressor failure.
Which doesn't stop the chiller to keep working with the other compressor(s).
That's the reason why I said that in practice the level of redundancy is comparable, in both alternatives.

Now, if I understood what Pascal is saying, he did experience problems with some multi-compressor chillers related to something else than the compressors, and if so, I have no reason to doubt it.
Every type of system has its peculiarities/weaknesses/strengths, I guess!

Cabo never installed a March pump in your boat. They didn't use them in the larger boats, only Scott style pumps like you have. I wouldn't run barnacle buster through the units for an hour, unless you want to buy new units as it eats away at the coils. H8eraide, I forgot the spelling of it, it's non toxic and and doesn't abuse the coils.

Rydlyme biodegradable descaler

My A/C company uses this stuff and has for the past 5-10 years. They've been in business 30+ years and a dometic/cruise air/marine air dealer for just as long. It's non toxic and biodegradable. I can never spell their name, so it takes some internet searching to find it. But they have a specific AC system flush, it talks about it at the bottom of this link, but I can't find on their website. They buy it by the 55 gallon drums.

Raw Water Flush - H8eraide High Performance Cleaners