Click for Furuno Click for Glendinning Click for Ocean Alexander Click for Cross Click for Delta

Running fresh water intsead of seawater through the AC units.

Discussion in 'Post Yacht' started by Davidoc, Jun 18, 2024.

You need to be registered and signed in to view this content.
  1. Davidoc

    Davidoc Senior Member

    Joined:
    Aug 29, 2005
    Messages:
    261
    Location:
    Winter:Delray Beach, Fl Summer: Bahamas
    I'm thinking of adding a fresh water intake to the Air conditioners. I'm tired of cleaning the strainer and heat exchangers in this hot, nasty intracoastal, salt water. Has anyone knowledge of the right way to tee in a freshwater line?
    Thanks
    David
  2. Pascal

    Pascal Senior Member

    Joined:
    Feb 29, 2008
    Messages:
    8,563
    Location:
    Miami, FL
    Where are you going to get the fresh water? Most marinas who’ll kick you out if they catch you ….
    RT46 likes this.
  3. rtrafford

    rtrafford Senior Member

    Joined:
    Jul 13, 2019
    Messages:
    1,753
    Location:
    Vero Beach
    That's crazy.
  4. rtrafford

    rtrafford Senior Member

    Joined:
    Jul 13, 2019
    Messages:
    1,753
    Location:
    Vero Beach
    Bromine tablets into your sea strainer basket....
    captainwjm likes this.
  5. Pascal

    Pascal Senior Member

    Joined:
    Feb 29, 2008
    Messages:
    8,563
    Location:
    Miami, FL
    Two different ac techs ( good ones I trust) recommended not using bromine tablets.

    instead I set up a valve system so I can back flush the coils with fresh water. In winter I back flush every 4-6 weeks… in summer every 1-2 weeks. Takes me less than 5 minutes for each chiller.

    also, have South Bay strainers (external strainer) completely eliminate the need to clean the internal strainer or eliminates the internal strainer altogether.
    Davidoc likes this.
  6. rtrafford

    rtrafford Senior Member

    Joined:
    Jul 13, 2019
    Messages:
    1,753
    Location:
    Vero Beach
    What was the reason for no-bromine? Do you recall? Bromine tabs in a stationary HVAc turned up while away no bueno, but with the chiller the pump runs routinely for chiller temps, so the Bromine never really builds up...
    Last edited: Jun 18, 2024
    Davidoc likes this.
  7. rtrafford

    rtrafford Senior Member

    Joined:
    Jul 13, 2019
    Messages:
    1,753
    Location:
    Vero Beach
    I have an external scoop/strainer fabricated on the hull, but still use the internal strainer, too. Replaced my strainer with a nylon version that is easier to clean and replace/dispose every six months or more. My gremlin is the buildup of film on the heat exchangers that needs Buster quarterly to stay ahead of a problem.
    Davidoc likes this.
  8. Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    13,486
    Location:
    Satsuma, FL
    While on our own first dock up Trout River, Jax, (over 15 years ago) I was going to shoot another shallow well down, just for some of the boats ACs.
    Never got to it and we moved back to Ortega.

    I do remember one hot summer in Ortega. Grass, barnacles, carpet grew over night in/on everybody's hulls & AC plumbing.
    Was a bad movie come to life what was growing in that dark hot water.
    I remember our diver talking about Berber carpet on the boat bottoms.

    Then we had a AC water pump failure.
    It was amazing what water options are readily available in the depths of an old Bertram hull.
    We were the only cold boat on that river for a while. Yes, some ACs can work on dock water.
    Now that I have told my only closest friends, you can't tell anybody.

    Then, we finally moved up (StJohns) river a few years ago.
    We have been blessed with our new up river location. Calm & cool spring water.
    No fouling and AC's run very well with cool fresh water going thru them.
    Thought I could rub that in to my close friends also.
    Davidoc likes this.
  9. Davidoc

    Davidoc Senior Member

    Joined:
    Aug 29, 2005
    Messages:
    261
    Location:
    Winter:Delray Beach, Fl Summer: Bahamas
    I'm paying for the the recycled water. I was asking if you know how to do it properly not where I get the water.
  10. Davidoc

    Davidoc Senior Member

    Joined:
    Aug 29, 2005
    Messages:
    261
    Location:
    Winter:Delray Beach, Fl Summer: Bahamas
    That wasn't helpful.
  11. Davidoc

    Davidoc Senior Member

    Joined:
    Aug 29, 2005
    Messages:
    261
    Location:
    Winter:Delray Beach, Fl Summer: Bahamas
    We do that. They only help for about 10 days here. Water is too hot and not moving well.
    Thanks for your nowledge.
  12. boatpoor

    boatpoor Active Member

    Joined:
    May 4, 2016
    Messages:
    249
    Location:
    32407
    I have a 3/4 full port ball valve on the pump outlet and a tee above that with a valve on the bench side that I connect to a garden hose. When I want to run fresh water through the system I close the lower valve and open the fresh water valve. Simple system that works fine for me.
  13. Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    13,486
    Location:
    Satsuma, FL
    This is confusing. If you have a non regulated fresh water supply there are valves to be manipulated; manually or automatically.
    I used a Red Hat 230VAc solenoid valve controlled by the pump relay. So the shore water was injected into the system vs the raw water pump turning on.
    If you have X fresh water flowing to your boat, valves and switches can be installed to make it work.
    The issue; thru 1/2 or 3/4", X supply may not flow enough for max BTU.
    Then high head pressures.
    In my post, was only able to run some ACs.
  14. Pascal

    Pascal Senior Member

    Joined:
    Feb 29, 2008
    Messages:
    8,563
    Location:
    Miami, FL
    Paying for 60 USG a day of usage at the dock is one thing… paying for 40 GPM is another.

    if you can’t figure out in 20 seconds how to hook up a tee and valve into your system…. Especially when you could not even bother giving us any info about the boat, number and type of units… do you really expect any intelligent answer?

    garbage in, garbage out.
    MBevins likes this.
  15. Davidoc

    Davidoc Senior Member

    Joined:
    Aug 29, 2005
    Messages:
    261
    Location:
    Winter:Delray Beach, Fl Summer: Bahamas
    Thanks. I was trying to come up with a solution when we're not close to the boat. The fresh water is pressurized as you know.
  16. Davidoc

    Davidoc Senior Member

    Joined:
    Aug 29, 2005
    Messages:
    261
    Location:
    Winter:Delray Beach, Fl Summer: Bahamas
    Thanks a lot Ralph for your helpful information. The configuration is the 46 post 1991. The system has two Cruiser air conditioning systems one for the salon and one for the forward State rooms. Salon is 16,000 BTU and 10,000 for the state rooms. A single March pump supplies both units with seawater from below the water line. The fresh water going to the boat is regulated. I'm guessing 30 PSI or maybe a little more. The inside diameter of the hoses used to pump raw water from the pump is 5/8 ID. I need to do the math on the volume of water available for each source. I didn't think there would not be enough from the freshwater Supply but you bring up a good point. Your system is exactly what I was trying to learn about. I'll do my homework thanks again.
  17. Davidoc

    Davidoc Senior Member

    Joined:
    Aug 29, 2005
    Messages:
    261
    Location:
    Winter:Delray Beach, Fl Summer: Bahamas
    Thanks I've been back flushing each unit as well. Unfortunately I have to pull the hoses off in order to do it and it does take me a while. I could Supply some fittings but I'm trying to reduce the labor it takes to take care of the strainer and the back flushing.
  18. rtrafford

    rtrafford Senior Member

    Joined:
    Jul 13, 2019
    Messages:
    1,753
    Location:
    Vero Beach
    Again, not a good idea in spite of the source of water to leave a pressurized water source connected to the boat from shore. Why do bromine tablets only work for ten days? Because after ten days they're dissolved? Bromine doesn't care about water being warm...
  19. rtrafford

    rtrafford Senior Member

    Joined:
    Jul 13, 2019
    Messages:
    1,753
    Location:
    Vero Beach
    Im not clear that you're digesting the issue I'm discussing, likely plaguing you some as well. Flushing doesn't remedy growth that commences within your coils. Warm water and an idle boat means that water has a solid opportunity to develop film on the coils and retard the value of the heat exchange. Hence, the quarterly barnacle buster soak...to clean the coils and remove the slime.
  20. rtrafford

    rtrafford Senior Member

    Joined:
    Jul 13, 2019
    Messages:
    1,753
    Location:
    Vero Beach
    Well, to be fair he corrected that issue with some healthy snark.