How fast does your...
 

cabin cool down when you run your air? I just tried out my new Mermaid 5200btu ac unit this weekend in the 353 and was a little disappointed. It ran straight for hours and never dropped them temp significantly. I put a digital thermometer in the supply vent and verified the temp at 64-65* (day). At night the supply temp got as low as 59* but it takes quite a while to drop that low. With an outside temp of 85* my cabin never dropped below 77*. Is this normal? I hear people tell me their ac will freeze them out, not mine? Should the unit be blowing cooler? Also, should the unit run for hours straight? :(

Re: How fast does your...
 

Try a small DC fan near the vent to circulate the air. It sounds like the fan moving the air is not strong enough to circulate.

Re: How fast does your...
 

My cabin cools down in a few minutes, once I turn on the AC.

Re: How fast does your...
 

Mine cools down in 10-15 mins

Re: How fast does your...
 

mine cools down pretty quickly, but i have a 7500 btu with 2 supply vents.

Re: How fast does your...
 

I don't have A/C on my boat but it sounds to me that you have a problem. A typical ac will put out at least 15 * cooler air than it's return. Possibly the problem is simply the return air is mixing with the hot outside air. If you can get to the condensing unit I would at least feel the larger line going into the compressor, it should be cold to the touch. If not you may have a problem. Also you may want to check your sea water lines for a strainer which may be plugged up.

If you have poor airflow typically the discharge air will be excessively cold this doesn't sound like the case unless the coil is froze up, then the airflow has been blocked by the ice. Try to turn the unit off for a few hours, try it again with the therm. and see what you get. If it has more airflow and a high temp. drop then you may be freezing the coil and need a tech. to check it out.

Good luck

Re: How fast does your...
 

I was told that my a/c would only be 10* below outside temp.i have a 5000 btu on the 37'

Re: How fast does your...
 

12,5K in my 28. I can make it snow. Drops 25 degrees in a 1/2 hr with the fan all the way up.

Re: How fast does your...
 

Sounds like you need to bring the boat to the dealer and let them figure out the problem. Hopefully it's under warranty.

Re: How fast does your...
 

After talking with Mermaid tech support they said "if it blows 18-20* colder than the ambient temp, thats the definition of ac". :mad:

Re: How fast does your...
 

I work on a/c for a living just not on boats. Similar but I am sure there are some special considerations taken for boats. I will try to help as much as possible.

-Typically an a/c unit will blow between 15-20* cooler air than it's return air temperature. If you got that then I guess it's ok.

-Again , check the return air ducts for any leaks which may be letting outside air into your air stream. A/c works on removing the heat from the air not adding cold air to the space.


-next question would be how big is the cabin? Generally 5 to 6k btu can cool a space approximately 300 sq. feet. (12k btu =1 ton of cooling = 600 square feet of effective cooling residentially) I know this is not the same with a boat but I would guess you still don't have 200 square feet to cool so I would think it is sized ok. Now check for any places that are not sealing out the outside air, That essentially adds load and could be the cause. If it's none of that than maybe you do need a bigger size a/c. But I find it very hard to believe unless your boat is black.

I hope this helps, Good luck.

Re: How fast does your...
 

Thanks for the info.....