AC Seawater Line Cleaning

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hmason

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Joined
Aug 9, 2013
Messages
2,764
Location
USA
Vessel Name
Lucky Lucky
Vessel Make
Pacific Mariner 65
We are in south Florida and are having a problem with reduced seawater flow from our AC discharge. What do you use to clean the lines and how do you do it? I've been told vinegar, muriatic acid, Barnacle Buster, Clorox etc., etc. Thanks
 
Here is how to do it:

Use Barnacle Buster, Rydlime, CLR or something similar. Dilute it 50/50. Then disconnect the hose from the seawater pump. Either elevate it until it is above the A/C condensing unit or get another piece of tubing that will fit tightly over the existing tubing so you can elevate it.

With a funnel, pour enough cleaning solution in the elevated hose until you can see it running out the thruhull. Let sit for an hour. Reconnect the hose and run the A/C for ten minutes or so to flush the solution out. You should see a stream of black *&^% pour out the thruhull for the first few seconds.

For really fouled condensers you might have to do this a couple of times. Or even better rig up a bucket and an old bilge pump and hook it to the discharge hose and rig a temporary hose from the condenser discharge back to the bucket. Circulate for a couple of hours, then flush as above.

David
 
I know Barnacle Buster works and David's suggestion to figure out how to circulate what ever you use is a good one.

Where in south Florida are you?
 
Has got me thinking my system probably needs it too, not sure how I would do it with 5 separate discharge through hulls.
 
Often it is the barnacles growing in the through-hull, strainer, up to pump. Cleaning the loop from pump through unit does nothing for the t-hull. That can be checked by disconnecting pump outlet and seeing what flow you get there.
 
Ski makes very good points. If you have a Perko strainer on the inlet (you should), and it is connected the right way round, don't forget that the debris and barnacles it catches are IN the basket and hence hardly visible from outside. Pull the basket, and clean the inside of the clear cylinder while you are at it.
 
First, in answer to hopcar, we are at Sunset Bay Marina in Stuart, FL.

As to N4712's comment, I am embarrassed to say we only have 3 discharges, although we dream of having 5 someday.

I clean the strainer regularly, put bromine tablets in as well. Next cleaning I will put in a Chore Boy copper scrubber as well.

I was thinking that I could run Barnacle Buster through the entire system by closing the through hull intake and pouring a few gallons into the system through the sea strainer. This would have the solution pass through the intake pump, the condenser coils and through all the discharges. Does anyone know if this would harm the pump in any way?
 
The advantage of using Barnacle Buster over the acids is that it won't harm pumps and strainers.

Stuart is a nice area. I want to spend some time fishing around there.
There is a great Italian restaurant in a strip mall on US1. I wish I could remember the name. It's on the west side of US1 about a mile south of the bridge.
 
Is the restaurant Marios? BTW, try 18 Seminole in Stuart downtown if you want a real italian treat.
 
Yes I think it's Mario's I'm thinking of.
I'll try 18 Seminole next time I'm up there.
 
Triton Marine makes a product specifically for this purpose, too. Said to be environmentally friendly. I've used it, with good results.

We also occasionally back-flush our system from the discharge outlets... using the shore-side water supply (and pressure)... when it happens we're temporarily on a floating dock.

I've read a small piece of copper (elbow or similar) in the sea strainer will discourage barnacle growth. Haven't tried that yet.

-Chris
 
I just did mine last season. I used a cheap pump out of an old shower sump I had lying around (cheap to by new too) and a 5-gall bucket. Powered it with a just start/battery assist box. Used proper descaler and setup a "loop" with a couple of hoses that bypassed the actual pump, yet circulated thru the whole system. Let it run for a couple of hours, dumped the water, repeated, then circulated clean water. pretty easy except the descaler has a rotten egg smell ;-)
 
,you also will need to check your water intake through Hull fitting. these can get fouled especially in the warm Florida waters
 
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