Clogged Air Cond Lines

[LMBoat]

Hello All,

I'm having a tough time cleaning out the air conditioning lines. I've heard you can flush muratic acid through them to clean them out. I'm a little concerned about doing this. has anyone done this? Will it hurt the hoses or the unit?

Thanks

 

[Southpaw II]

The most likely clog is at the intake, assuming the boat is in FL as your sig says. To be sure, take the line off the outlet side of the pump and turn it on to see if you have flow from the pump. Then go to the AC and remove the line to see if you have flow between the pump and the AC.

If it all checks, I think a MILD solution of acid would be OK to try.

Don

 

[fwebster]

A lot of people do use muriatic acid, but there is a risk, particularly with older A/C units. Muriatic acid will erode the solder joints in the cooling coil, so if you use it, you may develop some leaks. Most A/C guys will not repair cooling coil leaks because it is a sign that the entire system is borderline. The other issue with muriatic acid is the fumes while you are doing the work.

It is much safer to use phosphoric acid for coil cleaning. It is milder and won't attack the solder joints. Many paint stores sell it as a surface prep for etching. I use a 50% solution of phosphoric acid and water and just run it thru the system out of a bucket........when 2 gals of diluted phosphoric acid in pumped thru, shut down the system and let it sit for about 10 minutes, then start the system up and flush it with city water.

Do not try to do this with muriatic acid. If your system is really dirty and because of the risk of dealing with acid, it might be best to hire a professional to come and do it for you while you watch him so you can do it the next time.

 

[papertrail]

I cant imagine ever havint to use acid.


Simply disconnect hose from AC unit (and at bilge) and force water with a high pressure garden hose nozzle. (water exiting in bilge).
I have done this twice in 10 years. Has worked like charm both times.
Brian

 

[fwebster]

Cleaning marine growth out of A/C systems is a very common occurrence in warm salt water environments and a mild acid is about the only way. If all you have is silt from fresh or brackish water, freshwater flushing will help.

 

[LMBoat]

More info: I have cleaned out the sea-strainer and disconnected and cleaned all the hoses, and yes, have flushed everything with shore water. The last problem is in the cooling tube in one of the units. It does flow water, but not what it should. They are so tightly wrapped that is impossible to get a snake, cleaning wire, etc through to clean it out, so hence the acid option.

 

[Southpaw II]

More info: I have cleaned out the sea-strainer and disconnected and cleaned all the hoses, and yes, have flushed everything with shore water. The last problem is in the cooling tube in one of the units. It does flow water, but not what it should. They are so tightly wrapped that is impossible to get a snake, cleaning wire, etc through to clean it out, so hence the acid option.

I understand, but just to be clear, I was not suggesting the sea strainer was clogged. I was talking about the inlet on the bottom of the boat, and the line to the strainer. Did you disconnect the line exiting the pump to see that it flowed OK leaving the pump? Good luck.

D

 

[LMBoat]

Yes, it's clear. And the water flow to the other units is good.

 

[Southpaw II]

One last thing before you pour the acid to it.... very gently stick something into the water exit hose. Might be clogged by a resident insect or spider that ahs crawled in from the outside.

Don

 

[bahamabreisus]

We live on our boat, so with 3 units our pumps runs 24/7. So we had the same issues. After blowing out the lines with fresh water, we now put bromine tablets in the strainer basket. It seems to work great, all lines stay clear.

 

[HUMPH]

We live on our boat, so with 3 units our pumps runs 24/7. So we had the same issues. After blowing out the lines with fresh water, we now put bromine tablets in the strainer basket. It seems to work great, all lines stay clear.

That sounds like an interesting idea as long as it doesn't affect any of the components.

 

[Woody]

I know bromine is used in pools, hot tubs etc. It kills bacteria, and algae(I think), so I doubt it will hurt the AC components.