|Topic Review (Newest First)|
|03-29-2007 12:14 AM|
I have the Mermaid Marine Air heat pump system aboard (strictly AC on the dock even if I have the inverter, because it's an energy piggie: 10 amps for cooling and 17.5 for heat; 12,000 BTUs) and I wonder if the A-B fridge works on the same principles. I understand that it works with a differential between the water and the air temperature, and that it won't work if the water is below 40 F/5 C. Which is unfortunately when I'd want to heat the boat most!,
It's nice to have the A/C at the dock in the summer, but seriously, I'm thinking it's just taking up space in the long run if we want to go passagemaking. The only plus I can see is if we spring for a dock with power or maybe devote the entire Honda genset to it in order to cool off the boat. I suppose I could remove it and the ductwork, leave the vents in place, and gain a fair bit of stowage. I could repurpose the March pump as a backup pressure pump.
|03-29-2007 12:01 AM|
|EscapadeCaliber40LRC||My boat used to be plumbed that way. It had an 80 gallon fresh water tank dedicated as a cooling water source leaving us with just the 110 gal tank as the house supply. Thankfully hurricane Wilma came along and eliminated the electronics of my former compressor and I replaced the whole unit with an air cooled Danfross. I returned the 80 gallon to the house water system and rigged up a bunch of additional fans under the settee to help move air past the compressor on hot days. These four fans draw an additional .15 amps each and I can power them all on or off at will but usually I leave them off. My former unit was an Iso Therm.|
|03-28-2007 11:34 PM|
As a mechanical engineer I would be interested to see how much heat a certain sized water tank could absorb. My gut is with the previous posts that it would not be enough to be an effective heat sink. However, it is a fairly simple problem to work out if you have all the numbers. I'm a bit too lazy to actually figure it out for you. But, if you have any like minded nerds you know it might be fun to get out the old heat transfer text book and calculator to figure it out over some beers.
|01-28-2007 04:16 PM|
|PBzeer||Like Vasco, my intake is teed off another thru-hull. You do need to keep it below the waterline though.|
|01-28-2007 03:55 PM|
The water your system uses wouldn't be all that much warmer, since it isn't re-circulating the same water repeatedly, and adding heat to the same tank of water continuously... If you've lowered the cabin temperature by 10 degrees, you've put all that heat, plus some additional amount for th inefficiencies of the system into the water... If you only have 50 or so gallons to dump the heat into, rather than the billions of gallons avaiable in the ocean... the water will warm up rather quickly.
|01-28-2007 03:50 PM|
|Vasco||Interesting, are you going to drink it afterwards and I wonder if it'll warm the fresh water up. I have never checked my water cooled fridge to see how hot the water is when it goes over the side. I teed my cooling water intake off my engine raw water intake but I did put a through hull in for discharge but it was well above the waterline.|
|01-28-2007 03:50 PM|
This is probably not a good idea. The amount of heat the limited water tankage can absorb before becoming too warm to work efficiently is relatively low. The reason they use raw water, is that the system has an entire ocean or lake's worth of water to dissapate the heat into.
|01-28-2007 03:35 PM|
Refrigeration -Using the water tank as a cooling water source
Has anybody tried plumbing the Adler Barbour Super ColdMachine to the boat's fresh water system rather than using raw water for cooling? This way you would avoid another through-hull and the maintenance issues that go with using raw cooling.