Mold Prevention Chemical

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O C Diver

Guru
Joined
Dec 16, 2010
Messages
12,865
Location
USA
Vessel Name
Slow Hand
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Cherubini Independence 45
So I get mold growing on the supply vents from 2 of my 3 air conditioners. Not sure why one grows greenish and the other black mold, but not really relevant. The mold is only right at tthe vent, not in the supply hose or AC unit. Obviously I clean it up, but would like some sort of chemical / cleaner that would prevent mold growth for the rest of my boat ownership (I'm prepared to accept a shorter duration). The vents are teak. Any recommendations?

Ted
 
I have seen research that vinegar is good at killing and preventing mold, better than bleach especially on porous surfaces....and is less harsh.
 
The vents are teak. Any recommendations?

Did you soak or wipe the wood with any wood oil or treatment?

Some of them are mold magnets in the right environment. Pure tung oil, while great for wood in most cases, does that, as well as other wood oils.
 
Here you go

https://www.concrobium.com/

I use it at home and I am happy with it.

L
Lou, that stuffs MSDS shows trisodium phosphate as it's active ingredient if I am reading correctly....just in a premixed liquid.


So it's premixed TSP cleaning powder I guess. Not sure how it compares price wise.


Ted - a little researched showed this as a good preventer too, some recommend adding the powder to paint and other coatings to help prevent mold.
 
Things I have used with varied success on moldy wood,

Bleach. The change is instant as the visible part of the mold body is killed and bleached. The benefit is often temporary with the mold coming back quickly. I think this is because the bulk of the mold organism is left intact and alive just under the surface.

Vinegar. The change from moldy to clean appearance is slower than bleach requiring some scrubbing. The return of the mold is also slower. The main benefit to you is it’s less harmful to you.

Alcohol. Rubbing or denatured, not scotch. Much the same as Vinegar.

Borax. The old fashioned soap. Inhibits future growth of mold. Wash, scrub the wood with Borax wipe it off, not quite completely leaving a light film, just let that dry.

I rented a home years ago that had a terrible mold problem in the wood window frames and sills. The full technique was:
Soak with bleach.
Scrub with vinegar and let dry.
Soak with alcohol and let dry.
A soaking wash with Borax, let it almost dry, gently wipe up any visible residue.

I didn’t just pull this process out of my back pocket. It is based on a piece I read decades ago on wood preservation by the navy on minesweeper hulls. I no longer have that print out so I’m working from memory. According to the author the navy used glycol and borate. The glycol soaks into the wood and desiccates the fungus body (dry rot stuff) and the borate keeps it from growing back. My thinking is that fungi and molds are similar enough that the wood rot treatment should work on mold as well. And that I don’t want glycol where I live. And that borax soap is readily available and contains a salt of boron.
Google the key words “wood preservative glycol borax” and you’ll get more links than you have time to read.

As for how did it work? Well, mostly, sort of. I had to repeat the process several times before I got the mold knocked back enough to relax. If it were my house I’d have removed the infected wood and replaced it much the same as planking destroyed by “dry rot” has to be replaced.

Here’s a link disucssing the effectiveness of borax on mold “Does Borax Kill Mold

If the mold on your teak vents is severe the best option may be to replace the vents.
 
Removing the mold hasn't been an issue, Scotchbrite sponge, soapy water and elbow grease. Preventing the reoccurrence is my goal. Replacing the teak vent on one supply real isn't an option as its part of the built in seating.

Ted
 
Maybe try a tiny spot of water based polyurethane with a bit of TSP mixed in...I would only do it based on some more research...but a look and try might be worth it.
 
O C, take a look at this stuff...

https://www.rustoleum.com/product-c...ex-brands/mold-killers/mold-and-mildew-killer

Moldex. I have had good success with this stuff on my boat teak and my casita in Baja cleaning up after floods. This stuff can kill the hyphae that are growing in the teak and cause the reoccurance.

Generally, the black molds are "bad." Suggest a respirator for cleanup of that stuff.

Another moldy old thread on this...
http://www.trawlerforum.com/forums/s32/apparent-mold-nonskid-need-solution-please-28513.html
 
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Look at Obex. They make a treatment to remove the mold and a treatment to prevent it from coming back.
 
Tea Tree Oil.

Sounds like a concentration of water at the place where the mould grows.
Tea Tree Oil is expensive and only available in small bottles. I bought some in one of my most un-favorite stores .. Wall Mart. About $1.00 an ounce .. I think.

My wife makes a mixture of vinegar, baking soda and hydrogen peroxide. Takes black cap rails back to normal wood.
 
So I get mold growing on the supply vents from 2 of my 3 air conditioners. Not sure why one grows greenish and the other black mold, but not really relevant. The mold is only right at tthe vent, not in the supply hose or AC unit. Obviously I clean it up, but would like some sort of chemical / cleaner that would prevent mold growth for the rest of my boat ownership (I'm prepared to accept a shorter duration). The vents are teak. Any recommendations?

Ted




I don't know if this will work for you. I use it on my buildings and houses in places where I know I will have mold probelms. It sees to work well. It can be bought at most home stores.



https://www.amazon.com/Rust-Oleum-2...eff62698960246246559cc395da719&language=en_US
 
Practical Sailor did a test of mold and mildew cleaners/preventers and came up with their own formula that they said worked as well as the best store bought preparations. It's very inexpensive.

1 quart hot water

1 tablespoon baking soda (sodium bicarbonate)

2 tablespoons washing soda (sodium carbonate)

2 tablespoons trisodium phosphate (TSP)

I mixed some up and have used it in a few places. Now to see how well it keeps the mold from returning.

Ken
 
An internet search for fungicides formulat d for paint will provide several possibilities. I just ordered chlorothalonil (Daconil) to spray on our deck ceiling and posts. With high temperatures and humidity on the Gulf Coast mildew grows rampant. Not sure if it will work for my application but probably will. Check out internet DIY pest control sites which offer more choice than local hardware stores.
 
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Practical Sailor did a test of mold and mildew cleaners/preventers and came up with their own formula that they said worked as well as the best store bought preparations. It's very inexpensive.

1 quart hot water

1 tablespoon baking soda (sodium bicarbonate)

2 tablespoons washing soda (sodium carbonate)

2 tablespoons trisodium phosphate (TSP)

I mixed some up and have used it in a few places. Now to see how well it keeps the mold from returning.

Ken


i started using this formula a year ago and so far it seems to do the trick
Hollywood
 
We use dehumidifiers, keep the water out of the air and mold won’t grow. It is also more comfortable below.
 
I've used Moldex with good results in my lockers when I bought the boat. More mildew than mold though.
 
+1 on the Practical Sailor formula. Works very well. Wash off visible mold, letting it soak if necessary, then spray on light coat and let it dry. Best stuff I've used.
 
mold remover

I have the same problem...I run a commercial O-Zone Generator that cost 160.00 . It took care of the problem and works to keep the whole boat mold free and removes all odor's. I use it once a month. BE CAREFUL to" air the boat out" before you enter. Will cause lung damage if you breath in. Jp
 
I have the same problem...I run a commercial O-Zone Generator that cost 160.00 . It took care of the problem and works to keep the whole boat mold free and removes all odor's. I use it once a month. BE CAREFUL to" air the boat out" before you enter. Will cause lung damage if you breath in. Jp


If I’m not mistaken, O3 can also damage many kinds of rubber type products. So it could be a problem in a boat.

Rather than killing mold and mildew, I’ve had the best success with just getting rid of moisture. I have dehumidifiers for years in my boats and it works great. However, I’m always on shore power so I can do that. Currently, I’m using two small Peltier type of dehumidifiers on my boat. In the past I have used a compressor type of dehumidifier and just set one on the galley counter and have it drain into the sink.
 
Remove teak vents and replace with AL?

or

Remove and strip teak to bare wood and build up a few coats of CPES on it. Unlikely mold will grow there any better than AL.
 
Remove teak vents and replace with AL?

or

Remove and strip teak to bare wood and build up a few coats of CPES on it. Unlikely mold will grow there any better than AL.

The one with black mold growing on it is aluminum.

Ted
 
We are working on a house crawl space that has some mold starting.

The local contractors use both Rustoleum products , one after the first has dried.
Supposed to be better protection and smells far better.
 
The one with black mold growing on it is aluminum.

Ted

Ahhhh. Down here I switch off the ac compressor in my vehicles as I approach home to run air through the system to rid it of condensation. I too have noted the tendency in my last boat for condensation to collect on the AL louvres. Current boat has teak louves, and condensation seems to not be as big an issue.
 
Ted,
We delt with mold down here in the florida keys after hurricane Irma ( we had 4 inches of salt water in our house and they did not let us back in the keys for a week ). We researched the products available and asked the insurance companies and FEMA what we should use. this is what we found. Bleach was not a good product to use because it kills the mold but the by-product it leaves behind is food for more mold to grow. Products that worked well and we used were microban ( its called mediclean now ), and Concrobium. Concrobium has salt in it so not so great for metal.

Bud
 

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