Water cooled intake fouling and copper...

[skipgundlach]

Water cooled intake fouling and copper...

I searched and found no reference, whether 'Hooray' or "dangit", as to using some form of copper in the intake for water cooling of (in my case) refrigeration, or AC, to limit or prevent formation of critters.

One may buy copper wool in a variety of forms, but the one which looks like it wouldn't clog nearly as fast as the skeins of stuff intended for fine metal or woodworking is a common kitchen scrubber, of which there are SS, plain steel, and copper.

I am driven to distraction in fecund waters, with hard and soft growth taking over the tubing. Once past the 1" intake, diameters get smaller and take less time to foul.

Depending on where we are, that may mean total disassembly from the through-hull inward, and flushing it all with Barnacle Buster after the major stuff is removed.

But if copper is good for anti-foul paints, it seems that raw copper would be even better at discouraging critters until the water reaches the copper piping (which I presume would condition the downstream hose to the outlet, one I've not found fouled before).

I toyed with the idea of stripped wire coiled to fit down the pipe (I have a tee with a removable cap; it's needed if we are to get it cleaned out currently and would be an easy place to stuff whatever copper), but then thought about copper wool, having used steel wool before boat life; that led me to SOS pad musing, and upon investigation, I found that copper versions are readily available.

Just one of those pads would be enough to totally do perhaps 8-10 fills of my space (not so far down as to interfere with the through hull, thank you very much). A strip of copper screening, rolled so that water could easily pass might do the same job, but I gave the last of my screening away years ago and don't know where I could buy a small strip.

Anyone used this to either success or failure?

Thanks.

L8R

Skip

[Coolerking]

You realize that the seawater condensers of most systems are Cu-Ni right?
If you think that putting anything in the piping to somehow keep the growth down, while not clogging the intake...well....
All tubing gets fouled eventually
Engineer a clean out/flush kit setup for your boat and use it.
Also if you close the thru hull and leave it that way for a day or so, every few weeks, a clean system will stay that way, the copper poisons the water still in the lines and thus keeps it relatively clean.

[skipgundlach]

Originally Posted by Coolerking

You realize that the seawater condensers of most systems are Cu-Ni right?
If you think that putting anything in the piping to somehow keep the growth down, while not clogging the intake...well....
All tubing gets fouled eventually
Engineer a clean out/flush kit setup for your boat and use it.
Also if you close the thru hull and leave it that way for a day or so, every few weeks, a clean system will stay that way, the copper poisons the water still in the lines and thus keeps it relatively clean.

Perhaps I should have (I forgot the nature of the internet) said that I was only interested in personal history with the solution

But in case anyone else wonders, to get to my intake portion requires some gymnastics and physical pain (the only way to reach it is to have one knee on a 1.5" stringer, with my ankle (with shin at ~30° up angle) over the engine, and the other knee on the deck in the ER, with me upside down in the bilge), the less I have to do that, the better.

And, the cleaning modus is to disassemble everything to the point of the filter, take to a sink, and ream it before reassembly. Occasionally we have to run Barnacle Buster (I could use Muriatic Acid, but I don't like the potential on the metal) through the pipes and let it sit for a while, as the intake portion of the tubing (after the filter, before the coils) is about 5' long, and there's no practical way for us to make a loop, as is the normally recommended process to clean it out.

And, so far as we know, the outbound portion (affected by all that lovely CuNi) remains unsullied by fauna or flora, which supports the premise of "put some copper in the intake and your growth will be less" (or none, which would be lovely).

And, every time the reefer cycled, shutting off the intake of seawater, it would be only a couple of inches from the intake, thus treating any water below.

Or, at least, that's the theory. But I'm looking for RW experience to say, "Yes, it's just the ticket," or, "No, it made no difference," or something relative to my question

[tkeithlu]

Consider as a worthwhile small project your attaching a remote way to open and close your seawater intake. From your description, reaching the valve to stop a sudden failure down stream, a popped hose for example, would be close to impossible before the boat was flooded. Consider attaching a simple arm to the intake valve lever that lets you open and close the valve from a more accessible location. I think you'll appreciate having that capability every time you need to open or close the valve, independent of emergencies.

[skipgundlach]

Originally Posted by tkeithlu

Consider as a worthwhile small project your attaching a remote way to open and close your seawater intake. From your description, reaching the valve to stop a sudden failure down stream, a popped hose for example, would be close to impossible before the boat was flooded. Consider attaching a simple arm to the intake valve lever that lets you open and close the valve from a more accessible location. I think you'll appreciate having that capability every time you need to open or close the valve, independent of emergencies.

Thanks for the thought. It wouldn't work (impossible remote access), but getting TO it isn't a really big deal, while remaining over it for any length of time is.

That said, and entirely OT, I know someone who had a TH failure, and the vaunted tapered plug would not stay put. A magic eraser sponge, wadded and stuck in there did the job. Makes me nervous about all those plugs we have tethered to all the THs...

[chouliha]

Have you ever thought about using your freshwater tanks for fridge cooling? We did that about 25 years ago and it solved numerous issues. No fouling, eliminated having to check zincs, use of fridge while on the hard, etc. We are 100% happy with this method and would never go back.

[skipgundlach]

Originally Posted by chouliha

Have you ever thought about using your freshwater tanks for fridge cooling? We did that about 25 years ago and it solved numerous issues. No fouling, eliminated having to check zincs, use of fridge while on the hard, etc. We are 100% happy with this method and would never go back.

No, due to a variety of reasons, but I've heard others with good results, including keel cooler solutions...

[skipgundlach]

Over on the SSCA forum, I got this encouragement:

Hi Skip,

After having our heat exchanger flushed over a year ago when we bought our boat (it was in rough shape, could not rev the engine past 2300 RPM or so without over heating). I added short copper tube pieces directly into our Groco intake filter. They were cut from 1/2" copper pipe, are about 5.5" long, and I have 6 of them in there arranged around the filter basket.

It's difficult to assess how much it helps but the bowl has shown no growth and the old Yanmar runs at even temp even in warm water. I'm hoping that extends through the raw water system.

Dan
S/V Midnight Mile

[Flatswing]

I have had reasonable success also with copper fittings left over from home projects in the strainer basket, burnish them when I clean the basket quarterly. Some use pool tablets in the AC strainer basket (often liveaboards plugged in for AC) - theoretical risk to CuNi but apparently no worse than regular chemical flushes?

[sailingchiro]

When I haul for bottom coats, I buy some powdered copper to heavily mix with bottom paint to coat the insides of my thru hulls to inhibit growth. May work in your case as well. Just a thought.
So, instead of mesh, use heavily concentrated copper paint.

Another thought, I have covers (strainers) over my thru hulls, In which I hate (because they make it impossible to clean out barnacles) but they could hold some mesh that is replaced each bottom job.

If you are trying to just get copper in the thru hull, still like the paint idea.

BTW, the heavy copper paint does inhibit buildup between bottom jobs, it does require cleaning it out during bottom jobs. After painting, I also coat the valve with plumbers grease and work it in really well. Especially if it is getting hard to turn.

[Alan W Johnson]

In the real world, I have been using zinc oxide in the thru hulls for 30 years. It is a heavy metal and toxic to marine growth. I used to get tubes of it from a pharmacy. It was often used by lifeguards on the bridge of their noses to protect from sunburn. Now I go to the pharmacy to the baby isle and get a cream used on babies to protect their buns. I use one tube every year, spread it on a popsicle stick and apply to the inside of the thru hull. I never have any growths or barnacles.

Alan J S/V Skol C400