A/C kicking on and off...help!!

So with it being the summer in Florida I am dying now that my A/C isn't working ...The boat is a 2000 Wellcraft 290 Coastal, when I trun the Air Cond. switch on in the cabin the A/C kicks on and blows cold for a minute. I can hear the water pump kick on in the back but it doesn't start peeing water out the side. Then after a minute it shuts off.

Yesterday I tried it and it worked flawlessly for a few minutes then after shutting it off it never worked again for the whole day. Could it be a water flow issue or perhaps a freon issue??

Re: A/C kicking on and off...help!!

sounds like a water flow issue if its not running water overboard. compressor needs water flow to control head pressure . with low or no flow compressor will shut down.

Re: A/C kicking on and off...help!!

Is there anyway to test the pump?

Re: A/C kicking on and off...help!!

My first place to look would be the seastrainer. Make sure she is clean of debris.

Let us know what you find.

Re: A/C kicking on and off...help!!

Head pressure is regulated by waterflow, no water flow would cause the high pressure cut out shut the compressor off, pump problem or restiction in waterline or regulator valve.
Another cause for no water is that the head pressure is actually low and it's not calling for any waterflow, this could be caused by restriction in the airflow through the coil, filters plugged, fan motor bad, low charge, the low pressure switch would take out the compressor. Any deeper than that and you need a tech to look at system pressures.
Being that you do feel cold air at first my guess would be your low on charge.

Re: A/C kicking on and off...help!!

We checked the strainer and there wasn't anything there. I thought it might be the charge, but it worked flawlessly for about 30 minutes yesterday! I am beginning to wonder if there might be something blocking the water line.

Re: A/C kicking on and off...help!!

You can unhook the pump and run the A/C with a water hose. That will tell you where the problem is. The strainer can be clear and still not get enough water because of a plugged input. Also if the strainer is sucking air. Hook the hose to it.

Re: A/C kicking on and off...help!!

The small line (liquid ref) should feel about body temp maybe just slightly warmer leaving the condenser, it will get very warm to almost hot to the touch before the high pressure cut out takes out the compressor due to lack of cooling water. Low pressure will cause short cycling of the compressor and no heat felt on that same liquid line (leaving condenser).

Re: A/C kicking on and off...help!!

Thanks for all of the input so far. Let me explain the scenario a little more. The boat is kept in a wet slip. It was out of the water for several weeks having some repairs done. When we put it back, the problem started - everything would kick on fine and the air out of the vent would get cold, but only for about 15 seconds and then the compressor would kick out. The raw water pump would kick on, but no water came out of the thru-hull drain.

After sitting over night, we tried it again the next day and it worked great for about 30 minutes. The air was cold, the cabin cooled down, and it was pumping a strong steady stream of water out the side. After we took the boat out for a run and got back to plug it into shore power, the same thing happened as at first - it would run, but no water flow so it would kick out. I tried putting it to heat, so I think the thermostat is ok since the heat came on once I adjusted the thermostat to higher than the cabin temperature.

The strainer is clean, but it did get pretty plugged up about two months ago. I don't think there is an amp problem - I am on a 30 amp circuit and it is only drawing about 18 amps.

Re: A/C kicking on and off...help!!

Shutting down when there is a problem is a good thing.

Remove the discharge hose from the AC condenser (should be an 'out' arrow showing water flow direction). Backflush the system with a garden hose. You can get a layer of slime and crap in the lines that lets water flow thru, but not enough to let the unit remain cool. When you've reassembled the parts, run dish soap and bleach thru the system via the raw water strainer. Watch all of the crap that flushes out. If that doesn't solve your problem, there may be a raw water pump issue.

Re: A/C kicking on and off...help!!

I'm not totally sure about the marine type regulator valves, but typically a water cooled condenser has a regulator valve, it has a pressure sensing line and big spring, it varies the flow of water to maintain a set pressure, the valve is adjustable, it should be easy to spot.