Chiller recommendations

But if you don't have the extra air flow , you won't get the benefit of adding 12,000 btu. You may just circulate colder water until a freeze-stat shuts it down. You can't just pipe cold water around a loop for cooling, there are cooling coils in that loop with a fan/blower. Their just not technically evaporators, that happens in the heat exchanger in a chiller system, usually tube in tube but can be plate type. Are you going to use this system for heating also ? 5 ton chillers usually draw ~35 amps and are on 8 gauge wire (40 amp), I was just saying going to 6 ton you may need 6 gauge wire. Who ever recommended take your total heat load and install two compressor/ chiller units and 2 loops in case one fails. It's also possible to have just one cold water loop cooled by 2 chiller units.

You do have to consider the loop hose size and circulation pump size. Also need to consider the BTU's of all of the air handlers, because if they're not big enough the chiller will short cycle because the air handlers can't take anymore cooling from the loop anyways.

The

The loop, yes. I mentioned it earlier but not the refrigeration pipes which are part of the cooler

Chillers come in as needed. For instance on cloudy days or in the evening we usually have just one chiller running. The second one isn’t needed.

My point was that a small increase in chiller capacity may not require any upgrading although the chiller manufacturer would need to be given things like hose sizes, pumps flow etc to be sure

If the air handlers are 18 years old same as the chillers they may not be as efficient. We recently replaced all but one of our 17 year old air handlers and running on one 4 ton chiller, system is cooling much better. Also, had heat reflecting film installed on the ph windows which made a huge difference. Will see how it goes when it gets summer hot.

Could it be as simple as weak breakers?

Are there manuals with the Freq drives ?
Or can you download a manual from the net for your freq drives ?
Or can you post the make and model of the freqs here and see if we have more info ?
Usually these things have a trouble shooting guide and a directory of codes that should make your life better.

We have a different mfg, but had a problem with one new chiller not running after replacing both and reset the controller, has ran since. Try resetting the controller to factory default after all that work. Log all the current settings first.

+ 1

I don’t see the logic behind claiming frequency drive error could be caused a raw or chilled water flow error

Cruisair chillers have fairly extensive electronics that will log all faults and shut down the chillers. Not trip the drives

Were the drives replaced with the chillers?
Any errors logged in the chillers?
Did the tech look up the error code in the drive manual?
Drives have to be programmed by Cruisair, is it possible the new chillers require different settings?

You could also have air in the loop which can cause low flow and should give a shutdown default. We had a problem with air trapped in the salon loop lines that was hard to bleed without removing a lot of glycol. The thermostat control is programmable to run open for four hours to clear the air, it worked and the Spiro vent burped it out. Did the same for the PH air handler too. It is a good way to finish bleeding the system without diluting the glycol much, you should get a small pressure drop that takes very little make up water. Hopefully your thermostats have that capability because it works, the instructions will be in your manual.

I rebuilt with two Technicold 5 ton chillers. They've been running brilliantly for 3 years. Really well built. If I could have a mulligan, though, I'd be tempted to add a small chiller as the primary, perhaps 1 or 2 ton, and have it shut down and be replaced by the second 5 when called. It would cut down on a lot of the cycling, and likely extend the longevity of the 5's. The small would somewhat be sacrificial. Considering a 24v DC unit added to the loop in such a manner now. So many days so little effort is required to maintain the loop temperature. I think more research and calculation is needed here...

Yes, Technicold is quality stuff, 316 stainless throughout. Well done and good folks to deal with.

While reading my first guess was that the freon leak was within the heat exchange plumbing, and the gas displace water and created a lock within which she lost her prime on the raw side and overheated.

But again any issue with air in the loop or a seawater problem will trigger a shut down by the Cruisair electronics NOT the freq drive.

Need to know the meaning of the error code on the drive. Or the brand and model of drive to look up the codes.

Our Cruisaira use Telemecanic Altivars but that code isn’t in the manual so his must be a different brand

Didn't he say that it was tripping the breaker as opposed to signaling a code? There are times when my Technicold units will trip the breaker as opposed to tripping the high pressure safety. Always that's related to an air lock typically after I've cleaned the strainer or the diver has serviced the boat and somehow I've done something to lose raw prime.

If it's a breaker, that's my bet. If there is a code, that's another story.

He said it s the drive shutting down with a error code.

If a high pressure condition trips the breaker, something is wrong with the high pressure switch or the wiring.

Or sometimes the compressor just gets hot, and the breakers are sensitive to load. On the rare occasion that my breaker trips on the #1, I know what it is, and it's an easy fix.

True. Although compressors have thermal safeties and will shut down if they get too hot leaving no error code

For all we know his error code on the drive could be an over current. Checking the temp of the compressor is always a good idea

He is getting a F2F error which shuts both chillers down, need to know what code means. Mentioned low flow and raw water that the company worked on but decided not the issue. Still might need to log controller settings and reset to factory default. AC company can handle that or walk someone thru it, some parameter settings may need to be changed after reset. After reset ours has worked perfectly, though not a cruiseair unit.