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Ac/Heat Unit Question

1058 Views 6 Replies 5 Participants Last post by  JD
Our boat came with a SeaRay factory installed ac/unit in the V berth. It seemed to work well last year till about mid-way on our trip to PIB/CP. It heated up and scorched the wood on the cushion cover.

Other than I know (at least I am 99% sure as we have no generator) we have to be connected to shore power for her to work, I don't have a clue as to what I need to do for ac and for heat. Besides setting the controls and turning the switch on I mean.

For ac, do the engines need to be running? When it seemed to be working well last year for ac (beginning to middle of season) I was not running them. When the unit heated up and began pushing warm air and the heat scorched the wood on the bottom of the cushion cover, we turned it off and never turned it on again. I didn't know what I was looking for as a possible fix and no one I talked to did either. When I was cleaning the boat up in April for this year, I found the seacock to be solid mud. It is now perfectly clean. I don't know the condition of it when the unit heated up, but I tried the ac unit last night for about 10 mins and it got slightly warm, but not to the point were you couldn't touch it for a period of time. It was pumping water out the hull discharge with no problem. I am wondering if the seacock may have been clogged then and I did not know about it and the restricted water flow could have been my problem?

For the heat to work do the engines need to be running to warm up the water? I've heard it both ways, they need to run to heat the water and no they don't, as the unit pulls the heat from the lake water and hence, will not push air any warmer than the water you are in. I don't believe the water hose from the seacock to the ac unit runs through the engines, but I don't know. I never used it on this setting but would be nice for nights at the beginning and end of the season (and nights in between) to get the chill out of the air.

Thanks to any and all who can offer advice, as there are no marine ac companies around anymore.
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Sorry to hear about your problem, to answer your questions the engines do not need to be running to Heat or cool your boat. It is imperative that the unit be pumping water to cool the AC/Heat unit.

You didn't mention if there is a strainer after the seacock to collect any debris from the lake, that must be periodically cleaned if you don't it could become clogged.

I would try the unit in AC mode for a period of time if it is cooling properly the unit should cycle on and off once the desired temperture is achieved. The same holds true for the heat cycle. The cooling water is required for both cycles. Also this water line must be winterized every fall to prevent freezing.

The Marine unit is very similar to house AC/Heat pump except it is cooled by water in stead of air.
The engines have NOTHING to do with the a/c. It is 115volt only and yes, the clogged seacock was probably your problem. The function of the lake water is to COOL the compressor. It is like a reversable heat pump. During a/c or heat the water needs to flow freely to cool the compressor. When the water is very cold, like early April the heat will work, but just not that efficient.
not sure what year the boat is but i ran mine when i first got it without opening the seacock, it ran for a couple minutes than would trip off, safety trip so it wouldnt overheat, i wonder why yours wouldnt do that before it got so hot it scorched/burned things

i said seacock - he he
Thanks all for the input. You have pretty much confirmed what I had thought and that it turned out to be the plugged seacock
(I said it too). As for a strainer at the unit, I have no idea. I will be back out there in the next day or so and will really give her a once over, but from what I have seen so far, I dont believe there is one. The water coming out the hull discharge is a strong stream and appears to be garden hose clear.

As for the unit itself, all I can tell you is that it is a 10,000 BTU unit.

Thanks again.
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So tuesday I take the unit out of the boat and drop it off at J&S Marine Cooling systems on Jefferson, just north of Crocker and almost next door to Moonraker's. I talk with the owner, Jim, and he says to give him a couple of days. He calls me today, 24 hours later, and tells me that I had a hole in one of the tubes, and all the coolent had leaked out. He welded the hole, recharged and checked. No leaks and throws COLD air as well as WARM. I'm picking it up friday morning and putting it back in friday afternoon.

Thanks Jim at J&S.
Note of interest:
12 VOLT REFER (refrigerator) I know there are refrigerators on sailboats that are fan cooled (12 volt)and run on the battery. I rechargered one for my brothers friend at a Detroit marina for two cases of beer
and a night of sailing
. He and his family went on a two week cruise and has been running fine ever since.
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