Air Conditioning raw water clogging

[LSCalifornia]

Thought I'd share this recent discovery regarding Air Conditioning issues related to clogged sea water heat exchanger lines. Since I leave my A/C in de-humidifier mode when I'm not on the boat, it will cycle and drop the temperature in the cabin 2 degrees every four hours. This keeps the cabin amazingly dry however marine growth in the hoses reduces the sea water flow to the point that the system shuts down.I cut a T in the hose between the thru-hull and the pump and placed a ball valve on the T with 8' of 3/4" hose.I then close the through hull and open the ball valve and with the end of the hose as high as possible, I use a funnel and pour in a gallon of water and muriatic acid 70/30 ( this should be enough to replace all of the seawater with the acid mix.) I also place a 5 gallon bucket under the through-hull outlet to catch the acid mix ( I am not sure if it is an environmental issue so I play it safe) . I close the ball valve and let it sit for 15 minutes for the acid to neutralize. Open the through-hull, start the A/C and watch all of the dead growth flush out and return to full pressure. You can also blow through the hose before you start if the system is already backed up.

 

[Steve]

AC Question

Since my boat is 50 miles from home and the AC manual is on-board, what is the de-humidifier mode? Sounds like something that would come in handy during the high humidity summer on the Chesapeake.

 

[LSCalifornia]

The Dehumidifier

mode on Cruisair instructs the A/C to automatically runs for 15 minutes (fan only) to move the air around the cabin. Then the condensor turns on to drop the temp 2 degrees. It performs this cycle every four hours. It does not matter what the temperature is in the cabin ( except for freezing), just the act of lowering the temperature with air running through coils will pull the moisture out. This feature is activated by pushing the power and down buttons simultaneously while the unit on. I know that Cruisair has different thermostats and I have no idea if this feature is available on others or other brands for that matter. It should be because it's the best thing since sliced bread for keeping the cabin dry. All of the water that is pulled out of the air simply leaves the boat via the sump pump that handles the condensate water from the unit. Try the "TaylorMade Environmental" or your manufacturer's web site.NOTE.. make sure that your unit has automatic shutdown in the event of pump failure or clogging, otherwise use can burn your unit out and you would not know it until you returned to your boat.

 

[Tony]

HU Setting

I have used this since I got the boat and I agree it is great Don't even have lumps in the sugar dispenser!!!!!!!!!!!!!just push cold arrow and on/off simultaneously to engage itIt will read HU 1 when ont

 

[seadaddler]

HU1

I love it not having to run AC all the time when not at the boat,I don't pay for electric at marina but it is less wear on the whole AC systemand less chance of clogging when away from boat,I do check all my thru hull filters once a week.Nick

 

[GuyH]

nice idea!

my strainer gets clogged often, and I assume inside is getting clogged as well, but never could think of a way to flush it out..* Is there any concern about permanent damage to hoses & the A/C by the acid?* Did you think of this yourself, get from mfg, or other?thanks

 

[LSCalifornia]

Cruisair suggests

a muriatic mix. They don't say how to do it however. I am comfortable with the diluted formula on the hose and copper tubing, stainless strainer and plastic filter housing. March pump also said there should be no problem with the plastic parts in the pump. Again, as long as it's significantly diluted, and once fresh water and muriatic acid hits living marine growth, it kills it instantly. When I came on board to find the pump clogged, the filter was clear, so I am positive that the backup was either in the hose or the copper in the A/C.

 

[GuyH]

thanks...

nice information, I'm going to clean her out this weekend....

 

[Buck Harrison]

Lynn, et al

Although I have never had the raw water supply on my CruiseAir(s) clog up past the strainer, I too, have been concerned about marine growth occuring thru the remainder of the system and how to address the problem. Talked to H/AC guys about flushing w/ muriatic acid, but they basically didn't want to be bothered.At last years Annapolis Boat Show I put the question/problem to a CruiseAir rep. .... His immediate answer was ... "no problem, just put 2 to 3 small pool chlorine tablets in the strainer every month or so. Takes care of the problem".I've been doing that ever since last Fall. And, in addition, I have been putting a tablet in the condensate pan under the A/C unit (per the suggestion of my H/AC friend), to prevent algae growth there.Seems to be doing the job. The pressure of the exit water seems to be better than before. The strainer certainly has far less marine growth in it than it used to; hopefully the rest of the system does also. It's a simple solution that appears to work !

 

[Robert]

What does the chlorine do?

I use the 1 inch pool tablets in my dingy (in a small tupperware container with holes) and also in the gray water bucket in the bilge while cruising. They are great at getting rid of the gray water smell and the rain water in the dingy looks like pool water instead of the green sludge it used to be. The problem is when the chlorine level gets too high for too long. I once forgot to remove the tablet from the gray water bucket when I returned to the dock and a couple of months later it had dissolved the plastic Rule bilge pump. I wonder what it will do to the strainer, plastic strainer housing, and the hoses if left standing without use.

 

[Buck Harrison]

Robert

During the Summer months, when the growth problem is at it's worst, and we are running the A/C almost all the time, I put the chlorine tabs in the strainer about every 4-6 weeks and then let the system run for at least a couple of days. The tabs dissolve and flush thru the system within a day. During cold weather there is far less need to ck the strainer and I, like Lynn, use the HU1 function. I didn't put any chlorine tabs in during the Winter.

 

[LSCalifornia]

My take

on the chlorine tablets is that yes, it would most likely eliminate marine growth just as efficiently as the muriatic mix however the heat exchanger action must cause the same type of build-up in the copper lines as in an engine heat exchanger does and just like at a radiator shop, muriatic acid cleans the build-up right out.... a 16,000 BTU A/C generates a substantial amount of heat which must be exchanged with sea water temperature.

 

[Joe Wienecke]

refrigeration

would this work with the refrigerator also, I run it all the time and have notice the out flow is not as strong as before?

 

[LSCalifornia]

most heat

exchangers are copper tubing but I would always check with the manufacturer to be sure. I've found almost all marine equipment manufacturer's have great tech people that are quite eager to help..