AC flush connection

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Gilhooley

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Greenland
Greetings... the large lack of posts addressing my concern leads me to believe I am missing something big and am a mere few key presses away of once again appearing (I say "appear" as a form of dignity preservation) stupid.

So... I want to demineralize my AC systems... I have three fed by a single pump. The AC units and the exhaust thru-hulls are very hard to reach. To establish the recommended loops for Rydlyme circulation, I'd like to feed AC1 exhaust into AC2 and circulate while plugging AC3... then move AC1 to AC3 and repeat. I could do it internally at the internal side of the thru-hull but with my body, I will not be able to reach the the thru-hulls. Is anyone aware of a means of connecting one discharge port to another with a hose? I have a decent machine shop at home and can make anything I need but none of my ideas on this are feeling like they're worth much. Thanks.

G
 
When I did this, I took the hoses off the condenser.
Put on another 2 hoses
Held them up and filled them with muriatic acid and a funnel.

And really, mine were pretty clean inside.
Do you know you have a mineral scale?

After whatever time I waited, I put the hose ends in a bucket - pail to drain.

Make sure you have a fresh water hose ready to use, as it can burn you and other stuff...
 
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When I did ours, I just used the fill-and-soak method for the ACs.


Didn't try to establish a recirculating loop as I did with our mains and genset. Too hard to reach the discharge hoses at the outlets inside the hull, too much of a kludge to try to capture fluid outside the hull when would come out the discharges.


Clean the strainer basket and then flush the system with pressure water from the dock. One gallon or "product" in, let it soak, another gallon in, let it soak (pushes out some of the first gallon), another gallon in (ditto), let it soak... flush with pressure water from the dock.


I've used both Rydlyme, Barnacle Buster, and plain white vinegar... at various times. Each of the first two suggests a soak time. Latter needs more soaks, and needs changing more often.


-Chris
 
When I did ours, I just used the fill-and-soak method for the ACs.

Didn't try to establish a recirculating loop as I did with our mains and genset.
Clean the strainer basket and then flush the system with pressure water from the dock. One gallon or "product" in, let it soak, another gallon in, let it soak (pushes out some of the first gallon), another gallon in (ditto), let it soak... flush with pressure water from the dock.

Thank you Chris. I have quite a difference in heights for my AC units.. I think as the first one filled that I'd see the product preferring to head for the lowest discharge rather than coils of the upper two AC units... maybe. Do you think this is a reasonable concern? If your method is working for multiple AC units, I'm going that route. Thanks.

I've come up with a couple of easy to fabricate ideas for connecting loop-backs but I can't believe others wouldn't have done something with this before me.. or that the manufacturer doesn't put internal loop-backs in when they build the boat.
 
Where would I find instructions for flushing AC units? Mine haven't ever been flushed, six years now, and I had a marine tech tell me that flushing is not necessary in the PNW as long as the water flow is normal.
 
. . . . Is anyone aware of a means of connecting one discharge port to another with a hose? I have a decent machine shop at home . . .

I think you are considering temporary connections on the outside of the hull. Obtain two scraps of PVC sch #40 water pipe and machine a gentle taper on one end of each. Tap firmly into the thru-hulls from the outside and join with hose. Removal technique is up to you.
 
Just buy cheap garden hose and cut it to the lengths you need to go from the cooling water outlet nipple of each units coils to a central bucket. Then stick a bilge pump in the bucket and feed its output throught the manifold that feeds the three units and circulate the acid.
 
Thank you Chris. I have quite a difference in heights for my AC units.. I think as the first one filled that I'd see the product preferring to head for the lowest discharge rather than coils of the upper two AC units... maybe. Do you think this is a reasonable concern? If your method is working for multiple AC units, I'm going that route. Thanks.


Yes, that system works with multiple ACs -- two, in our case -- on one pump. When the system is filled with product... at least, in our implementation... it's everywhere, not just low spots. Our two units are also mounted at different heights, but once product is flowing out the discharge outlets... the whole system is pretty much full. Our discharge outlets are oddly located. Both are near the bow, forward of the AC pump. The discharge for the saloon AC, way aft of the pump, is the furthest forward discharge, and the master berth outlet is just aft of that. No clue why, unless that was all about somehow equalizing (almost) head pressure on the whole system.

You can inexpensively/easily check how much product is necessary to fill your system by pumping a known quantity of dyed water (food dye, etc.) through the system. I learned from our winterizing process that 1 gallon nearly fills our system, including the strainer... so pushing a few gallons through sequentially, one at a time without flushing with fresh water in between, cleans, flushes, and ensures the system is full of product for the recommended time.

First time I did it, I used Rydlyme, and lots of goo came out. Since then I've used vinegar... and Barnacle Buster... not so much good from those.
OTOH the first time I did it (2 years ago, I think) was the first time it had ever been done in 14 years or so. The other time was recently (last couple weeks), and I was more focused on the mud -- and the sea nettles (jellyfish) in the strainer basket -- than anything else.

I suspect CLR would work. Or a dilution of inexpensive muriatic acid from Ace Hardware or similar... or there's a similar product Home Depot sells called Prep N Etch. I've read elsewhere that Marine Air actually recommends a dilution of muriatic acid, but I haven't noticed that in our Marine Air documentation.

-Chris
 
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I used Barnacle Buster on my 225 Lehmans. Saw a 5 degree drop on the port engine and a 10 degree drop on the starboard engine. I did the fill and soak for 7 hours as I did not have an easy way to make a closed loop to recirculate the BB solution, I did not want to remove the water pump impellers since the starboard pump impeller is very difficult to remove and replace. I used the Sea Flush adapter to put the solution into the strainers, it worked great.

For the A/Cs and the generator, I am going to use adapters called Trac Flushcaps that fit the Groco ARG strainers that temporarily replace the strainer covers and use a garden hose to bring the solution in.

I can also use both of these to inject antifreeze into the engines, A/Cs and generator when I winterize the boat next month.
 
Had an AC guy tell me to put a half of bag of Pool Shock into the raw water strainer and let the AC run for an hour.
 
Had an AC guy tell me to put a half of bag of Pool Shock into the raw water strainer and let the AC run for an hour.


Can't see how that would be effective. The stuff would cycle all the way through and out in about 1 minute or less?

-Chris
 
Can't see how that would be effective. The stuff would cycle all the way through and out in about 1 minute or less?

-Chris
I could see it killing stuff...but not removing the scale/calcified stuff/barnacles, etc.....
 
The shock actually slowly dispences because it is granular and heavier than water
 
The shock actually slowly dispences because it is granular and heavier than water

It will dissolve soft living growth, but will not dissolve mineral scale.
I never seen algae, seaweed or anything like that growing in our AC lines.
 
I use bromide tablets in the income water sea strainer. They last long enough that there's always some left when I have to cleaner the grass out of the strainer. The bromides keep the crustacean growth from happening. I only need to do a muriatic clean if I've been spending too much time away from my boat. Spending time away from my boat I try not to do. I've heard it can affect ones mental health.
 

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