Marine Air Systems A/C

[ranger58sb]

Originally Posted by Doorpro

One thing does come to mind and it is pretty far fetched but who knows. You see when I removed the hose from the unit that would flush through the hull I attached a hose to the dock so I wasn't seeing what came out originally so who knows there may have been an obstruction that got blown out and I know this is very unlikely but hey, I've got a cold galley so I want to thank everyone that got involved and believe me when I tell you that every reply helped me, so thank you all. Watch this space, i'm still not convinced.

Sounds plausible to me. If everything continues to run OK, even with all three units simultaneously, I'd by the "it was blocked, and you cleared it" theory.

And I'd still consider doing a full descaling of your systems, to possibly improve it even more.

-Chris

[GordMay]

The active ingredient in Rydlyme is Hydrochloric acid, commonly known as muriatic acid.
The active ingredient in Barnacle Buster is Phosphoric acid.

[Doorpro]

Ok guys,

I had forgotten to finish this thread by letting everyone know that although I didn't see anything come out of the hoses when I flushed the unit there must have been something there because the unit has been acting normal for weeks now.
I'm sorry that it took this long to both let everyone know this but also to thank for all your input.
Thanks again,
Doug.

[Badsanta]

Thanks for the update

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[Pgutierrez]

Hey, It Works!!! Marine Air Systems Passport 2,16,000 BTU on 2000 Catalina 36. Sailed in Lake Michigan & Upper Mississippi River. This the season to get this thing going! Below is my learning curve and now works on my boat. Some of these suggestions are obvious, but might get overlooked.
1) Do you have healthy water discharge? Check water flow system, from water intake to water discharge for obstructions (zebra muscles might be clogging hoses, valves, screens, fresh water filter filled with algae). You might have to ream out hoses for obstructions.
2) The heat exchanger, aka evaporator coil) water flows through a box with filled with a copper pipe, surround by freon), air is drawn by the blower over the fins of the evaporator. Heat from the air is transferred to the refrigerant (freon or similar). The heat is transferred to the fresh water and heated water discharged. Hope your coils feel really cold. If you have your windows and hatch covers open, you will only invite too much moisture in and you CAN freeze up the copper pipes -if you freeze up, there is a defrost cycle on control panel for the heat exchanger. You will never cool the boat if you are inviting hot humid air to easily enter cabin. Close boat up, hopefully you have a hatch cover alternative - my boat came with zippered hatch cover, snaps in place, with clear plastic flexible plastic window material.
3) if your boat has been in high mineral content waters, there could be a calcium build up in heat exchanger. Disconnect both upper and lower hoses for heat exchanger. Plug discharge pipe with 24" clear hose and insert funnel to other end of hose. Raise funnel above the top of heat exchanger and Pour vinegar in the funnel until it comes out the heat exchanger on the top (muriatic acid or lime away scares me - vinegar is much less toxic to the environment and your hands). Secure funnel end so it remains above the top of heat exchanger and let the vinegar sit for a day (or a week). Vinegar will dissolve any calcium deposits in the exchanger.
4). One reason your AC system might not be working is because there may be air bubbles somewhere in the water lines. My set up has a small valve on the discharge side of the pump (between the pump and the hull) that allows me to discharge a small stream of water for a few seconds to purge any air bubbles out of the system (yes, the fresh water hull valve must be open).
5). Make sure return air grill next to the heat exchanger (in the cabin) is clean. The return air grill will be at floor level in the main salon. You should vacuum it or wash if possible with fresh water. Cat and dog hair stuff these grills up.
6) Make sure the cold air grills in all cabins are un obstructed (yes, this past weekend a family member conveniently put a book or magazine covering the grill.
7). Read your manual or download and keep printed copy on board.

[Doorpro]

Pgutierrez,

I thank you for your long and detailed help with this matter but I feel that It was all in vain.
If you have taken the time to read the comments and help from other forum members you would have see that this issue is sorted a long time ago.
This doesn't mean that your input isn't important and I thank you for the time that It took for you to try to help with my issues.

regards & thanks,
Doug.

[Pgutierrez]

Doug, this is what I posted on the Catalina 36 web site today. Thought it might be useful to others. A repetition of subjects never hurts. There are newbies for all categories/ subjects / sub subject topics. Hope this helps some one.

[transmitterdan]

Pgutierrez,

Some of your terminology may lead to confusion. For example, the part of the unit with water flowing through the heat exchanger is a condenser not an evaporator. The evaporator is the cold part of the air conditioner where the air blows through. The evaporator coil is a place where dirt and mold can build up. Keep it clean for highest cooling efficiency and air cleanliness.

A proper cooling water intake should be well below the waterline at all angles of heel such that no air can get in. If air bubbles are getting into the cooling water something is wrong with the design or the piping from the through hull to the pump has a leak. Almost all air conditioner water pumps are not self priming and should be below the waterline and thus never need priming (aka getting the bubbles out).

[Pgutierrez]

Sailboats heel over when sailing. Air bubbles may sometimes - two truckloads of a grade animal feed nonfat, 40# bags, light to cream in color, $0.50/#.


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[170122]

Originally Posted by Doorpro

Hello all,

about 5 years ago I bought two Marine Air Systems VTD12KZ-410A units to replace two rusted out units and one of them has worked flawlessly since day one. The other has been working off and on for the past couple of years and I have checked almost everything that I know to check.
Firstly I have checked the water pump and it works fine and feeds the unit. It is a huge pump feeding five units through a manifold and when I turn one or all five A/C units on the pump starts and strong flow of water is evident and the other four units run flawlessly so I'm thinking that the pump and plumbing is fine. I have also had the diver check the through hull and I have checked the strainer and they are both clear and clean.
I should say that the unit that I am having trouble with will run for a couple of days with only one HPF fault early on when starting the unit and then will run great but then on most days like today I turned the unit on and it starts up for a second or two and then shuts down with the HPF fault showing and today the unit has not kicked back in after a minute or two like it will sometimes do. I have noticed that the moment the HPF fault is registered the water pump turns off however the fan will continue to blow.
I think that I have mentioned most things going on here and I hope that someone can give me some insight on where the look next. I have had the cover off of the controller to see if there was a loose wire to the pump but all seems fine in there although the control unit may be bad but I have no way to test it unless I remove the one that I know is working and try that on the malfunctioning unit.
I have read a few threads here and one mentioned running city water through the condenser and I was wondering if I should try that and if I should is it as easy as removing the hose from the pump and attaching a hose to run fresh water through the unit?
Any help will be gratefully appreciated and I thank everyone in advance for looking at this thread.

regards,
Doug.

Time for descaling, do the ones having issues, create a loop using your oil change pump, barnacle busters 5:1 will not damage the welds inside your coil, please do not use muriatic acid!