AC spitting out white "sand"

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cardude01

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Nov 26, 2012
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Bijou
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2008 Island Packet PY/SP
AC spitting out white "sand"

One of my AC units constantly blows out some white "sand" looking stuff. The fins on the condenser/evaporator seem to be corroding and I think some of this corrosion is being sucked up by the fan and it's blowing out of the vents, looking like sand.

Is there a procedure for cleaning off this corrosion? Some magical chemical? It looks pretty bad.

Also, I wonder why this unit has so much corrosion. It's not that old-- 7 years.
 
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Yes, there is a fin cleaning solution you spray on the fins and it cleans them very nicely. Think you can find it on Amazon. Google air conditioner evaporator cleaner.

Ted
 
I googled cleaners and came up with a huge list. Didn't know if there was a specific one most folks used.

I assume the fins are disintegrating because of moisture trapped in the dirt between the fins. Wonder if there is a solution that would stop the corrosion ?
 
I think regular use of the cleaner goes a long way toward prevention also, but make sure that the way you A/C is connected that it is not being utilized as a sacraficial metal in your bonding system.
 
I think regular use of the cleaner goes a long way toward prevention also, but make sure that the way you A/C is connected that it is not being utilized as a sacraficial metal in your bonding system.


I don't know enough about bonding systems to check this. How do I check?
 
You can pick up coul cleaner at Home Depot. The cap on the coil cleaner is a brush that not only cleans the coils very well but also makes a good fin straightener.

It sounds like your fins may be corroding away. At some point salt air can destroy the fins completely.
 
PENGUINS!!!!

giphy.gif
 
AC spitting out white "sand"

You can pick up coul cleaner at Home Depot. The cap on the coil cleaner is a brush that not only cleans the coils very well but also makes a good fin straightener.

It sounds like your fins may be corroding away. At some point salt air can destroy the fins completely.

Ok. Cool. I'll check at HD. Thanks.

Yeah. It looks like the fins are going away.

I wonder if there is a corrosive inhibitor I could spray on them to slow that down? Something not sticky.
 
Ok. Cool. I'll check at HD. Thanks.

Yeah. It looks like the fins are going away.

I wonder if there is a corrosive inhibitor I could spray on them to slow that down? Something not sticky.

Anything you spray on them is going into the air you breath. As well as flowing on and around the rooms and the things in them. Plus if it's even remotely sticky the fins will end up a dirty mess in a fairly short time I would think.
 
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My guess would be the white stuff is actually aluminum oxide. This is likely the evaporator coil fins corroding. Moist chloride laden air may be the culprit.
 
Hmmmm. I did clean the bilge after replacing a macerator pump with bleach. Maybe that's it.
 
My guess would be the white stuff is actually aluminum oxide. This is likely the evaporator coil fins corroding. Moist chloride laden air may be the culprit.


At the boat today. The lower corner of the Evap fins are definitely corroding away. Sheesh.
 
Clean and rinse, light spray with CR-56 or any other light oil. Yep will get dirty in time just clean again when it does. Mine look like new and are several years old.

The bleach you used may be the cause. I know of someone who used pool acid (muriatic) to clean his garage floor and nearly ruined several bikes, two sets of pasture pool clubs (golf) along with most of his tools with the fumes.
 
I don't believe bleach is the issue. He cleaned his bilge with it not the coils.

Salt air is most likely the issue. Lots of people run their A/Cs with the doors or windows open. Even if it's just in the fan mode to move air around the units pull salt air through the coils and the coils rarely get washed off. So the fins corrode away.
 
I was thinking about the fumes as he said it just seemed to get worse, I know that in closed spaces bleach fumes are quite corrosive as it produces chlorine gas, a salt.

My fins are wet with water/condensation (flowing into the pan) and I would think that would do a fairly good job of rinsing the evaporator coil while in use and keep salt accumulation in check.


While corrosion has been identified as his problem, you are also correct, my goal is to delay it somewhat with a spray coating long enough for the unit to die from some other cause.
 
Use the Cobra AC Cleaner. It goes on as a foam. Then you use a hose with light spray and rinse the dirt away. Usually takes a couple of applications.
 
Use the Cobra AC Cleaner. It goes on as a foam. Then you use a hose with light spray and rinse the dirt away. Usually takes a couple of applications.


I did. Washed away some of the fins in the process as I rinsed. Hopefully that helps. Thanks!


Pretty much everything I touched today went to sh$t for some reason. Full moon?
 
Greetings,
Mr. 01. IF you're having one of those days you should have realized it at 11:00 hrs so you could have started drinking at noon and not touched anything else except for the cooler lid and the zip top.
 
Yeah I know. I was so damn frustrated but hated to quit.

Finally gave up around 3pm and had a cold beer.
 
If your fins are washing away as you clean them, I hate to say it but you may be well on your way to new handlers.
 
AC spitting out white "sand"

Wow. Great. ?
 

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