A/C not very cold


Seaduction

Seaduction

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We occasionally turn on the A/C to make sure it is working, but noticed the air is not very cold. Air is really not even cool, but not warm either. How cold should the air be coming out?

Is the A/C unit easy to access on the 310SS (2012) and is there a way to test and refill the freon? Is this a do-it-yourself project?
 
So in your new boat you really should NOT have a leak....there are tests to do.

But I think someone in these threads are TEMPS that are normal, something like 50's or so. It is a bit warmer than auto's...plus it is not Freon I believe anymore. It is also dependent on the inside temperature.

You do need special tools, but they can be had.

I am sure additional experts will chime in....

This article might help...

http://www.powerandmotoryacht.com/systems/how-troubleshoot-your-boats-air-conditioning-system
 
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Just checking -- per TAG.. and the instruction manual, when the water temp gets near, or above 90 degrees, the AC becomes less efficient. Not sure where you are so wondering if that's an issue??
Rick
 
Toofast, thanks for the article...that helps! Not sure why, but my expectation was the boat's A/C air would be comparable to my automobile A/C...sounds like it won't even be close.

The air from the A/C outlet seems cool, although not much. Water temp is typically in the 80's so that may be part of the problem too. Cabin is usually hot when we turn it on and usually do not run it long, just a few minutes to make sure it works and the overboard raw water discharge is working. Strainer is checked and cleaned once a month.

I have never checked the filter or the condensate pan (not sure where they are located). Since the A/C has only been turned on for 5-10 minutes a few times a year, these 2 items are probably ok. Does anyone know where these are located on a 310?

If the filter and pan are in good shape, would you suggest I have the refrigerant checked by a pro? Sounds like refrigerant is rarely an issue.
 
So I bet you have no problem....

The filter and the condensate pan are right in front and underneath the unit.

The filter is just a thin piece of plastic, that has fine mesh like covering...if you've never cleaned, that could be an issue. It is RIGHT in front of the unit, between it and the back of the seat, it will just slip out the top.

Also, if the cabin is HOT, say 85, then air coming out will be 65 or so....
 
Toofast...thanks!

I believe the A/C unit is located in the small crawl storage space in my cabin, aft of the head and under the helm. Is that where you access the filter as I cannot find it anywhere in the cabin?

According to Dometic's diagram, it should be located right below the supply air grille but is not there (see attached).
 

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So the filter is NORMALLY right in front of the evaporator coil - in the very front of figure one in your picture.

It is super thin black normally plastic like filter. It just lifts up....
 
it will take longer than 10 minutes to get the temps down in the cabin. I usually turn it on, uncover and wash the boat, by that time the cabin temp has dropped.
 
Thanks for your help!

Formula TAG said there is no return vent in my cabin but is on the unit as you described toofast, accessible by entering the crawl space behind the cabin steps and under the helm, a real pain to get to! Hopefully, the filter does not require cleaning too often.

I'll clean the filter, then let the A/C run for a while. This is my first boat with A/C, so I was expecting the air to come out fairly cold like my automobile's A/C, but obviously that's not going to be the case.
 
Mine stops getting cold when the sea strainer starts to get clogged with algae. In the summer months when the water is warm this can happen in as little as 3-4 weeks. This makes a huge difference even though the raw water output from the boat does not visibly change that much. I also run barnacle buster through the raw water portion of the a/c and allow it to sit for an hour or so. It cleans out all the crap that grows in the raw water portion of the a/c unit. You'll be surprised how much stuff comes out in the raw water when you start it back up. That really makes a difference on how cold the unit will get.
 
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Checked filter and it is very clean.

How do you get barnacle buster into the raw water portion of the A/C lines since the pickup is from the boat bottom?
 
You'll need a 3-4 foot long piece of hose and a bucket. You can get clear piece of hose from west marine that is the same diameter as the hose that runs from the strainer to the a/c raw water pump. Probably 1" inch.

Make sure the a/c is off.
Close raw water seacock.
Remove the hose at the a/c raw water pump that comes from the sea strainer.
Connect the clear hose to the a/c raw water pump. Other end goes in bucket.
Fill bucket with barnacle buster.
Turn a/c on. A/c raw water pump should pull barnacle buster solution into a/c unit.

*You may need to open the bleed valve at the pump to prime it and/or initially hold the clear hose up with barnacle buster in it until pump begins to pulll in solution. Once it starts to pull simply put the end of hose in bucket with solution.

Once you see it being discharged out of the thru hull fitting out the side of the boat turn a/c unit off.
Thats how you know the entire raw water portion of the a/c system is filled with the solution.
Let solution sit for an hour or as needed.
Disconnect the clear hose and reconnect the original hose from the strainer.
Turn a/c unit on. Raw water will flush out barnacle buster.
Watch discharge at thru hull fitting to see what comes out with the solution.

I originally used muriatic acid and water solution, but then read it is not recommend. But it works.
 
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Checked filter and it's clean. I have to believe that odds of a refrigerant leak are pretty slim. Will run A/C next time I'm out and see how it cools down after 10-15 minutes.
 
Yes, remember, it is really a heat exchanger vs. a car AC unit.

Next time, measure the cabin air temp....then turn on the AC and measure the temp coming out of the vents, then let us know.

That will tell us everything....

Oh Water temp as well, as that has an impact!

We will get her figured out!!
 
toofast said:
Yes, remember, it is really a heat exchanger vs. a car AC unit.

Next time, measure the cabin air temp....then turn on the AC and measure the temp coming out of the vents, then let us know.

That will tell us everything....

Oh Water temp as well, as that has an impact!

We will get her figured out!!
Click to expand...

For reference. What should the difference be between the two temperatures?
 
Usually the temp difference before and after the evaporator should be 15-18 degree temp drop.
 
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