[C320-list] Through hull for new AC unit

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Jack Brennan

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Jun 21, 2021, 11:33:41 AMJun 21
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Hello all:

We’re thinking about installing a self-contained AC unit in the fall. I have a question about the through hull that is needed.

Can I tee off the engine through hull, or does proper installation require a new one in the port locker?

Jack Brennan
Sonas, 1998 Catalina 320
Tierra Verde, Fl.



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Doug Treff

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Jun 21, 2021, 11:46:44 AMJun 21
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I don't know about "proper, but mine has a dedicated through-hull in the compartment near the prop shaft, and the water pump is located there as well. The line runs along the compartment where the strut bolts are and a hole was drilled through the aft bulkhead into the rear compartment. Water output is on the sugar scoop next to the propane locker drain through-hull.

--
Doug Treff
do...@treff.us

Brian McLamb

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Jun 21, 2021, 11:52:00 AMJun 21
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Mine is like Doug’s except the discharge is on port side at height of the
port stern locker shelf. Works great. I believe the a/c mfg probably has a
recommendation for size and location of this. Brian. S/V Serenity #1075

On Mon, Jun 21, 2021 at 11:33 AM Jack Brennan <jackb...@bellsouth.net>
wrote:

> Hello all:
>
> We’re thinking about installing a self-contained AC unit in the fall. I
> have a question about the through hull that is needed.
>
> Can I tee off the engine through hull, or does proper installation require
> a new one in the port locker?
>
> Jack Brennan
> Sonas, 1998 Catalina 320
> Tierra Verde, Fl.
>
>
>
> Sent from Mail for Windows 10
>
> --
Brian McLamb

Doug Treff

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Jun 21, 2021, 11:55:24 AMJun 21
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Now that I think about it, you definitely should not tee off the engine through-hull because the suction of the engine pump could pull air through the AC water line and cause your engine to overheat.

--
Doug Treff
do...@treff.us

Jack Brennan

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Jun 21, 2021, 12:28:32 PMJun 21
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I probably won’t do it because I need to haul out in the fall or early winter for a bottom job and can get the through hull installed then.

But what I was wondering about was a Y valve at the engine intake through hull. Considering I wouldn’t use AC underway, the flow could be shifted to one direction the AC and the other for motoring.

The biggest danger, I suppose, would be forgetfulness. But sometimes there are other downsides you don’t discover until you implement your “great” idea.

Jack Brennan
Sonas, 1998 Catalina 320
Tierra Verde, Fl.





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Bruce Hunter

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Jun 21, 2021, 12:42:03 PMJun 21
to C320...@catalina320.com, Jack Brennan
I tee'd off the engine cooling seacock after the sea strainer. I also put a ball valve before the A/C cooling pump and another on the hose going to the engine's water pump. We keep our ignition key in the area of these valves.
Bruce HunterNauti Time 719

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On Mon, Jun 21, 2021 at 12:28 PM, Jack Brennan<jackb...@bellsouth.net> wrote: I probably won’t do it because I need to haul out in the fall or early winter for a bottom job and can get the through hull installed then.

But what I was wondering about was a Y valve at the engine intake through hull. Considering I wouldn’t use AC underway, the flow could be shifted to one direction the AC and the other for motoring.

The biggest danger, I suppose, would be forgetfulness. But sometimes there are other downsides you don’t discover until you implement your “great” idea.

Jack Brennan
Sonas, 1998 Catalina 320
Tierra Verde, Fl.





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From: Doug Treff
Sent: Monday, June 21, 2021 11:55 AM
To: c320...@lists.catalina320.com
Subject: Re: [C320-list] Through hull for new AC unit

RONALD HODEL

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Jun 21, 2021, 12:43:52 PMJun 21
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Just a thought! If you’re going to air condition the entire boat you need a dedicated AC unit, obviously and the questions you’re asking I’d be interested in hearing the answers to as well. But if you’re only gonna air condition the sleeping cabin (My wife and I sleep in the stern) I’ve often wondered about using a Zero Breeze Mark 2 unit. They’re expensive but cheaper than a dedicated AC unit and they can be powered by their own battery pack which means you could use it at anchor and charge it during the day with solar. We don’t mind heat during the day but getting to sleep at night, it would be nice to be a little cooler. I’m sure it wouldn’t bring the aft cabin down to freezing if you’re after that but 25 degrees cooler and dehumidified would be nice. I didn’t hear good reports about the first unit but apparently the Mark 2 is an improvement. It’s certainly couldn’t do the whole boat, that’s for sure.

Ron Hodel
Lokomaikai #1070

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> On Jun 21, 2021, at 9:04 AM, Doug Treff <do...@treff.us> wrote:
>
> Now that I think about it, you definitely should not tee off the engine through-hull because the suction of the engine pump could pull air through the AC water line and cause your engine to overheat.

Doug Treff

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Jun 21, 2021, 12:58:19 PMJun 21
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Apparently, it's a common enough practice to cause Groco to make a manifold to meet the demand.

https://www.groco.net/products/fittings/manifolds/raw-water-manifold

I guess having less holes in the boat has it's merits. Still, I would seek the advice of a surveyor on what is acceptable. You WILL need a survey at some point, either for insurance reasons, tr to sell the boat. Might as well do it "right" the first time.

--
Doug Treff
do...@treff.us

On Mon, Jun 21, 2021, at 12:28 PM, Jack Brennan wrote:
> I probably won’t do it because I need to haul out in the fall or early
> winter for a bottom job and can get the through hull installed then.
>
> But what I was wondering about was a Y valve at the engine intake
> through hull. Considering I wouldn’t use AC underway, the flow could be
> shifted to one direction the AC and the other for motoring.
>
> The biggest danger, I suppose, would be forgetfulness. But sometimes
> there are other downsides you don’t discover until you implement your
> “great” idea.
>
> Jack Brennan
> Sonas, 1998 Catalina 320
> Tierra Verde, Fl.
>
>
>
>
>
> Sent from Mail for Windows 10
>
> From: Doug Treff
> Sent: Monday, June 21, 2021 11:55 AM
> To: c320...@lists.catalina320.com
> Subject: Re: [C320-list] Through hull for new AC unit
>

Jack Brennan

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Jun 21, 2021, 1:39:24 PMJun 21
to C320...@catalina320.com
The funny thing about insurance is that I’ve never been asked for a survey, even though I’ve owned sailboats off and on for 40 years in Florida.

<rant>It’s probably just as well, because most of the surveyors here aren’t worth a damn. After shelling out 1K for a worthless survey on my 320, I decided I would self-survey from now on if I ever buy another boat, although I suspect this one is it.

They don’t check the diesel, they don’t examine the rigging. In fact, they tend to turn a blind eye to all but the most trivial of problems because if they slam a boat too hard, word gets around among the yacht brokers so they don’t get any referred business.

Mostly, they just turn things off and on to see whether they work, tap a few obvious spots on the deck to find saturated core in places where it’s not important and ignore all of the haphazard wiring that could catch your boat on fire one day.

I bought my 320 from a bank that had foreclosed on it, and the supposedly reputable surveyor missed almost all of the sabotage that someone had inflicted on the boat, either to get revenge on the bank or just for the thrill of vandalizing.

In fact, he didn’t even find the stuff that I had already identified before hiring him. It was lucky for him that he asked for the check before he wrote the report.</rant>

Dave Hupe

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Jun 21, 2021, 2:01:00 PMJun 21
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We have a 16,000 btu unit that both cools and heats.  The unit sits on the port locker shelf.  There is one air discharge vent that dumps all the cooled/heated air into the main salon just above the refrigerator. An return/intake air grill is located on the port wall of the aft bedroom. This setup will cool/heat the entire boat, but you must leave the aft bedroom door open to create a circuit of air.  You probably could also install a vent grate in the door to do the same thing if you wanted the door shut.
A separate  water supply thruhull is in the bottom of the hull very close to the engine water thruhull.  I believe you could use a Y off the engine thruhull, but would ALWAYS need to be able to select ONLY one route at a time.  As another commenter said, you don't want to suck air into the engine cooling circuit  back thru an open  AC circuit, nor do you want to run the AC and suck water back from the idle engine circuit.
My AC water discharge is thru a port side thruhull just slightly lower than the port locker shelf.
You also will need to deal with getting rid of water condensate. My condensate accumulates in a pan under the compressor and gravity drains (not well) out a rear small thruhull above the swim platform.  I recommend instead a separate active pump with float or sensor for the condensate that works regardless if the AC is running or not.
Dave Hupe1994 #32

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Melissa&Larry Leibman

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Jun 21, 2021, 5:15:11 PMJun 21
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I initially ran a T off of the engine through hull for A/C cooling as a temporary measure before I hauled the boat at the end of the season to install the extra seacock (of course with a ball valve to isolate the circuit; however, I have no ball valve in the engine side of the split; so when the A/C is running is could theoretically suck water from the raw water cooling circuit).

10 years later the T remains, and I’ve never had a problem. There is more than sufficient cooling water for the March A/C pump used to cool the A/C (albeit only a 12K BTU unit with appropriately sized cooling water pump). I have a garden hose connection in the line from the ball valve to the A/C pump to remove any air that might accumulate but I’ve only had to use that after launch or once when a sea nettle clogged the filter.

I once even forgot the close the ball valve before starting the engine, and although I remembered before it ran very long, it seemed to be keeping cool just fine. I think the flow through the engine intake is sufficient even with the ball valve open.

That said, I would guess that a dedicated through hull and strainer is called for by ABYC, and if anyone asks that is my recommendation. Furthermore, I keep some spare hose aboard in the event the A/C sucks something into the through hull that I cannot blow out, I could draw water from a different through hull like one in the head.

I still plan to install that separate through hull ………. 😊

Larry

Onat Dogruer

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Jun 21, 2021, 5:37:03 PMJun 21
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Hi all,

Happy to share my perspective as a fellow 1998 Catalina 320 owner and ABYC
certified technician. In theory you can tee the engine intake as long as
the engine and the A/C doesn't run at the same time -with a proper Y valve
that seals perfectly. The critical issue here is the volume of water
traveling and in absence of enough water -- as others mention -- there is
the likelihood of air entering the system. A 3/4" engine seacock will not
yield enough water for the engine and A/C at the same time. Both A/C pumps
and engine pumps are centrifugal, designed to run flooded only, meaning
they cannot run dry or handle air blockage. That's why these pumps need to
be installed below the water level. It's okay to do it if you have a large
seacock with enough volume and appropriately-sized manifolds. Typically we
don't run these A/Cs continuously like larger yachts. Professionally, when
I do A/C installations onboard our size sailboats, I do install a separate
seacock, and that is what I recommend. It's a neater set-up and easier to
troubleshoot.

Jack, feel free to message me if I can be of further assistance -- happy to
help.

Best,
Onat Dogruer
1998, #546

Archer Power Solutions
odog...@archerpowersolutions.com
https://www.archerpowersolutions.com/


On Mon, Jun 21, 2021 at 12:28 PM Jack Brennan <jackb...@bellsouth.net>
wrote:

> I probably won’t do it because I need to haul out in the fall or early
> winter for a bottom job and can get the through hull installed then.
>
> But what I was wondering about was a Y valve at the engine intake through
> hull. Considering I wouldn’t use AC underway, the flow could be shifted to
> one direction the AC and the other for motoring.
>
> The biggest danger, I suppose, would be forgetfulness. But sometimes there
> are other downsides you don’t discover until you implement your “great”
> idea.
>
> Jack Brennan
> Sonas, 1998 Catalina 320
> Tierra Verde, Fl.
>
>
>
>
>
> Sent from Mail for Windows 10
>
> From: Doug Treff
> Sent: Monday, June 21, 2021 11:55 AM
> To: c320...@lists.catalina320.com
> Subject: Re: [C320-list] Through hull for new AC unit
>

Jack Brennan

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Jun 21, 2021, 6:05:42 PMJun 21
to C320...@catalina320.com
Thanks, Onat and everyone else

That’s good advice. I’m trying to understand all of the issues before I commit to anything. There’s nothing worse than doing a project and having someone say, “Oh no, you really didn’t do that, did you?”

Jack Brennan
Sonas, 1998 Catalina 320
Tierra Verde, Fl.




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Troy Dunn

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Jun 21, 2021, 9:21:02 PMJun 21
to C320...@catalina320.com
Couple thoughts.

Thru hulls are too easy to add and I can’t imagine it’s cheaper to go the
manifold route. Besides, you also need an outlet so…nah, keep it simple.
We have a brand new Dometic Turbo 12K. drop in replacement for the DX-12
we had. I did replace all hoses as a preventative maintenance procedure. I
ordered MPI 5/8” aircon hoses. Not easy to source, we ended up buying a
box of 50’ hose but this is truly "the good stuff". The electronics for
the AC are All SMX-2 compatible on the control side so didn’t have to
replace the control panel. IF you spend any time living on the hard in
coldish climates (probably not an issue in FL), check out Flagship marines
products. They use the good old fashion hair dryer approach for heat
which means you don’t need water for the heating function AND one less part
to break (the reversing valve) on the HVAC side. It was tempting but who
am I kidding…I'm not sleeping in the boat for fun in the winter.

As far as surveyors go. Jonathan Sands is in Fort Lauderdale last time I
checked. We flew him up to Maryland to survey Wonky Dog on the
recommendation of friends. We had a fantastic experience and would gladly
pay the airfare again to have a proper and unbiased marine surveyor look at
our boat. Agree that asking around with the folks selling boats can get
sketchy and although I suspect most of the surveyors are fine..it does feel
a bit like the whole business is a circular argument. Kinda like the
bareboat certification process…

FWIW

Troy Dunn
Hull #514
Wonky Dog
Rock Hall, MD
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