Clogged AC raw water hose

[bradf]

Hello Tugnuts! The aft AC raw water discharge appears to be clogged on our R-31. The forward AC raw water discharge is flowing freely, but the aft discharge right next to it is piddling out. According to the manual the aft discharge comes from the AC unit in the main cabin.

Not sure what is causing the obstruction, I'm guessing marine growth of some kind. I clean the raw water strainer regularly and have used bromine tablets to keep the marine critters in check.

Seems that getting to these AC hoses to remove, inspect and clean them is going to be a bear of a job. Can anyone offer advice on this?

Thanks!

 

[Bosn Mate]

Good morning:

Believe we met at the rendezvous in Feb - if so, the Battery Daddy is going strong!

We had the same issue on our R29. We created a closed loop system with a pump in a bucket utilizing the AC priming pump and AC discharges which circulated Barnacle Buster. Very easy to do.

We are currently in the St Pete area looking at marinas for a future trip. PM us if you would like to discuss.

Mike and Kathy

 

[bradf]

Hey Mike! We sure do remember meeting you and Kathy at the rendezvous. Glad you're getting good use from that Battery Daddy! 🙂

I'm familiar with the Barnacle Buster treatment. It's the preferred and recommended method according to the AC manufacturer. Seemed a bit cumbersome, perhaps easier than I thought. Incidentally, the manufacturer does not recommend Bromine/Chlorine tablets. They are corrosive to the system.

Where do you connect the hoses to create the closed loop? I seem to remember you installed ball valves for this purpose.

Brad

 

[Bosn Mate]

Brad:

I created a process to flush the ACs upon return from our typical 3 month cruises while Tingira is out of the water and on the trailer. Hopefully this will be adequate along with regular fresh water rinses when in the water. Also, this process flushes the whole system without cutting hoses for flush attachments.

Process as follows:

* Installed a ball valve close to the AC strainer to be used if the system lost its prime.
* Bought a submersible pump, recycling bin, hoses, and Barnacle Buster.
* Closed AC strainer.
* Placed submersible pump into recycling bin; think the bin is 8 gallons.
* Attached hose from submersible pump to AC primer valve.
* Inserted two hoses into AC discharges on hull starboard side; the hoses fit snug and don’t leak. Placed loose hose ends into recycling bin.
* Filled recycling bin with 5 gallons of Barnacle Buster.
* Activated submersible pump and circulated Barnacle Buster per instructions.

Mike

 

[KKRCRACE]

What I have done on two occasions when I had blockage before sea strainer is close valve, tape up the end of a cut off garden hose so it fits the intake side if the strainer, stick it in and hold it tight and at the same time open sea strainer valve and turn hose on. For me it blows out the blockage or growth and the AC works afterwards.
KKRCRACE

 

[knotflying]

I would first check that you have no blockage at the intake or in the lines. I would try forcing water with a hose into the outlet and let it go through the system out through the seacock. Make sure the intake below is clear of growth and barnacles. You can also close the seacock remove the filter cover and open the seacock to see if the flow looks good. Also when forcing water from the outlet you can observe the flow as well. One you determine that the blockage is internal growth then do the barnacle buster routine.

 

[NwRecon]

I had an issue with my R23 AC once when I shut down power without letting the system shut down first by using the control panel. The next time I tried to use it, NO WATER FLOW out of the discharge port. I read the manual and all the way in the back I read that the water shutoff valve in the AC unit might get stuck in the closed position and if the happens, tap or slap the unit with your hand and it should release. On mine I crawled in the cave and was able to reach up the side and slap it. I heard a plop and tried the AC again with positive results.

 

[Texas Tuggernaut]

I use a garden hose with a shut off valve with a 5/8” hose barb on it. Unhook the discharge hose from the pump, put in the hose barb, tighten the hose clamp to hold it on and then slowly open the valve on the garden hose. City water pressure is typically enough to flush out any gunk in the hoses and AC. Watch the AC discharge when you turn on the water and you can see what comes out. If this doesn’t restore adequate water flow then the more complicated Barnacle Buster treatment will do it.


Sent from my iPhone using Tapatalk

 

[bradf]

Thanks everyone. I really appreciate the great advice.

Restricted flow is coming from the cabin AC discharge only, the v-berth AC discharge is OK. So the clog appears to be in the branch of hose that feeds the cabin AC unit. I'm guessing that there is a T-fitting in the raw water line that branches to the two AC units? I'm also guessing that it's going to be really hard to get to!

A ball valve between the sea strainer and seacock makes sense, if nothing else to rinse the raw water system with fresh water after use (which I've never done). Also to circulate the Barnacle Buster treatment.

Less clear is the hose attachment to the overboard discharge ports for the Barnacle Buster treatment. The boat is in a slip and it's not easy to get to those discharge ports. I may need to go for a swim. Then there's the issue of getting the hoses fitted to the ports so they stay in place?

Thanks again for the help on this.

 

[fishheadbarandgrill]

This is the simple procedure I used to pickle my A/C raw water circuit. Purchased an extra stainer cap and used a drill and soldering iron to open a hole in the end of the cap. Inserted a nylon hose barb (NPT to barb) into the hole and used epoxy to seal. I then purchased a 5 gallon plastic bucket, drilled a hole and inserted an adaptor with an other barbed end in the bucket. connected the bucket to the end of the modified strainer cap with nylon tubing.

I then closed the seacock and filled the bucket with barnacle buster. Raised the bucket high enough to give it enough head pressure. Eventually the barnacle buster pushed out the raw water in the circuit and I let it sit for 6 hours. I tinted the barnacle buster with food coloring so I could tell when the BB was coming out the discharge ports. When done pickling, reverse the process and run the A/C to clear out the BB.

Pictures in the my next post.

 

[fishheadbarandgrill]

Pictures of my A/C circuit pickling with Barnacle Buster.