Flagship marine chiller water AC ?

[Pascal]

Does anyone have experience with Flagship marine Air Con systems? I m seriously considering upgrading the Air con system to chilled water. All of my air handlers and condensers are now 20 years old or more and I have two bad compressors. The others won't be far behind...

The simplicity and redundancy of chilled water is very attractive and they are now used on much smaller boats than before

Running new water hoses from the ER to each air handler isn't a big deal as the ER is right in the middle of the boat.

Flagship has 36k Btu chillers at $4k each, I d need two instead of 4 or 5 smaller traditional splits. Each air handler run around $1000/1200 depending on size. Because the gas only runs in the chillers it seems to be a lot easier to maintain

 

[GCSI]

The insulation requirements of the chilled water lines are often overlooked or "minimized" by salesmen. Properly done, it's an extensive project that's not as easy a pasting on some Armaflex. Keep in mind, if there is any breach / hole / weakness in the insulation, the pipe will sweat profusely. Also consider the expansion coefficients when selecting materials: you'll be dealing with up to 80* F temperature deltas.

 

[Walter P]

Sounds like the right way to go. Be sure to keep us posted .....

Walt

 

[davidwigler]

Check the price on the pumps and controls. I looked into it several years ago and I seem to remember coming to the conclusion it would be around $30,000 for parts only. It's a very efficient system though, if you plan to cool or heat the whole boat. You might find a 24K Compressor would cool the whole boat at night and both of them would run in the heat of the day.

 

[Boatsb]

If I was starting from scratch I'd probably use keel coolers to replace the raw water. Less trouble in the long run.

 

[Angela]

I got a quote for a chiller system once before. Not only did we determine that it was cost prohibitive, running the chilled water lines to every room was just not feasible since the water lines, once insulated were about 2" diameter. No way we're we going to try to muscle that to four staterooms, galley, PH, salon, etc. It's hard enough to pull a friggin' wire in here. However, with your boat all torn apart with the dark, evil spaces now exposed, it might be more doable for you than for someone like me who was trying to change the system with gutting the boat. That is why I went the self-contained route. Plug and play.

 

[Pascal]

Indeed in my case running the pipes is not a big issue since it will be done before the carpentry is finished..

I put in a self contained in the saloon a year and a half ago and it's jsut too loud. Maybe yours are a little quieter but still the compressor makes some noise.

Keel cooler have obvious benefits but I wonder where you'd mount it on a hatt. Not anywhere near the keels due to the tanks, so it woudl have to be under the flatter surface of the hull. Would have to look into this

I also thought costs woudl be very high but it's not so bad compared to splits. I m tird of patching up the old system, I have replaced one compressor and or one air handler every year so far. And that rack with 5 hard to reach condenser is a mess.... The copper piping is 45 years old.

Flagship build their units here in Florida using US made components. Looks like good quality....

 

[oldawg]

Indeed in my case running the pipes is not a big issue since it will be done before the carpentry is finished..

I put in a self contained in the saloon a year and a half ago and it's jsut too loud. Maybe yours are a little quieter but still the compressor makes some noise.

Keel cooler have obvious benefits but I wonder where you'd mount it on a hatt. Not anywhere near the keels due to the tanks, so it woudl have to be under the flatter surface of the hull. Would have to look into this

I also thought costs woudl be very high but it's not so bad compared to splits. I m tird of patching up the old system, I have replaced one compressor and or one air handler every year so far. And that rack with 5 hard to reach condenser is a mess.... The copper piping is 45 years old.

Flagship build their units here in Florida using US made components. Looks like good quality....

Google Fernstrum grid coolers. Used a lot on workboats.

 

[krush]

You'd want a chiller with variable capacity. This may mean multiple compressors, or variable speed compressor, or unloaders etc.

Make sure the cold water lines are all run in places that if they do sweat, it won't damage anything.

Also, I would install everything so it could also be used to pump hot water if you ever want to do heat....just hook up to an engine or genset (add a webasto or aquahot is another option)

 

[Pascal]

The way it's done according to manufacturers and installers is you use two or three chillers, in this case probably two 36k connected in parallel. The system brings the second one on line as needed. Flagship recomends copper pipe with foam insulation. No big deal to set up

And yes, redoing the whole system means having the ability to set it up so its easy to service

They have a reverse cycle option as well as heating elements in the air handler. I don't use heat more than 3 nights a year, I may just add a heating element in the master

I think chilled water is the way to go when you have access to upgrade the plumbing and eventually will replace splits in original installation. I be seen new 50 footers using chillers whereas 8 years ago you d only see them over 65/70

 

[Boatsb]

When properly designed and installed it can be an excellent choice. My $.02 says no for the simple reason of service and maintenance access on a refit does not usually reach the standards found on new vessels. The original design was though out pretty well and adding newer similar technology should improve it.

To re invent the wheel is a very large undertaking and may not work as well as expected.

 

[scallywag]

Keel cooler have obvious benefits but I wonder where you'd mount it on a hatt. Not anywhere near the keels due to the tanks, so it woudl have to be under the flatter surface of the hull. Would have to look into this

Hey Pascal. Here is some food for thought. Of course you remember Panacea's keel cooler setup after the sweaty run from Fort Myers to Islamorada 4 or 5 hears ago. It turns out Panacea's keel cooler configuration is undersized for the BTUs required down here. There is just enough square feet of surface area on my keel cooler for the 90 degree water (freakishly hot!) we get in Florida Bay.

So, I ended up plumbing a 120,000BTU heat exchanger from Flagship Marine ( http://www.flagshipmarine.com/heatexchanger.html ) in-line and I'm very happy with the performance/serviceability. Raw water is pumped only through the exchanger in the engine room. The old fresh water loop remains flowing through the rest of the boat and I replaced all 7 stand alone units with larger capacity Ocean Breeze units. The AC units are only fed fresh water and should last a long while. I also added an 8th 24,000BTU unit in the engine room fed raw water. (I now have 127,500 BTU throughout the boat and can keep things very comfortable)

The benefits are:
1.) Longevity of the stand alone systems since they will only touch fresh water. No descaling and minimal maintenance.
2.) The retrofit was only about $2500 for the heat exchanger.
3.) Mega redundancy. If one AC unit goes out I have 6 others working. Of course I carry a spare pump.
4.) Multiple zones. This keeps humidity very low and allows me to crank the air con in the summer and keep it a meat locker if I want to.
5.) No chilled water loop insulation issues. A friend of mine's chilled water install in his 82' Broward ended up with lots of wood damage due to condensation on the chilled loop lines!
6.) Raw water is in the engine room only. I like it that way.

My buddy runs an 82' Broward with an Ocean Breeze chilled water system. He had a nightmare of a time with the first two chillers, but replaced them last year and everything is great now. It turns out his boss bought some frankenstein units that were converted to marine by Ocean Breeze and they were both "duds". The new units are flawless and even look completely different than the old ones.

Personally, I have nothing but good things to say about Ocean Breeze

(BTW My install configuration is a little different now. Moved the raw water pump)

 

[Pascal]

Yes I remember your set up... Wasn't here a leak in the keel cooler too?

So yours are all in one units, with the compressors thru out the boat, right? I like the idea of a heat exchanger instead of a keel cooler although I feel that with chillers you re limiting the descaling issues to only two or three units so it's not a big wall every couple of years.

I m getting the point on proper insulation...

 

[scallywag]

Yes I remember your set up... Wasn't here a leak in the keel cooler too?

Yes, actually three pinhole leaks on the 20+ year old weld seams. Welder fixed it right up.

So yours are all in one units, with the compressors thru out the boat, right? I like the idea of a heat exchanger instead of a keel cooler although I feel that with chillers you re limiting the descaling issues to only two or three units so it's not a big wall every couple of years.

Yeah, all in one units throughout the boat. There is practically nothing ever to descale though on a fresh water loop. Scale is buildup of calcium and other goodies that are constantly flowing through the seawater system. The more seawater flows though the system the more goodies are introduced and it builds up over time. On a fresh water loop there is only the trace minerals in the water in that loop and no more are ever introduced, so scale doesn't build up over time. This applies to both fresh water heat exchanger systems like mine, or a chilled water systems.

A good chilled water setup has two compressors for redundancy and increased summer loads. You have the freshwater loop pump and sea water pump that could fail, but spares can even be plumbed in with a manifold and "the show goes on". Descaling and other maintenance becomes much easier and the air handlers require practically none besides filter changes.

I m getting the point on proper insulation...

Insulate the heck outta that chilled loop. I highly recommend doing the plumbing yourself. By my experience, even the best installers will cut a few corners to get home in time to watch the Heat game. As with many things "If you want it done right, do it yourself.", but somehow I feel like I'm preaching to the choir.