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Advice on refridgeration unit please

On Fri, 18 Jul 2008 18:32:48 +0700, Bruce in Bangkok
wrote:

Thanks Bruce,
This is the sort of information I am looking for.

It's a pity about the wind in that area. I always have to smile when I
see people hiring the Sunsail yachts out of Langkawi and then motoring
everywhere. Still, not a bad place to motor around the Islands and
then up to Siam.

In Curacao the trades blow non-stop. Even disconnected from the mains
and relying on the one 80 watt solar panel (16 years old) and the new
Airex wind generator, it keeps the batteries charged no matter my
usuage and the charging light goes off indicating a full charge quite
often during the day.

Need some of those trades back home.

cheers
Peter
On Fri, 18 Jul 2008 18:14:20 +1000, Herodotus
wrote:

On Fri, 18 Jul 2008 12:06:49 +0700, Bruce in Bangkok
wrote:

On Fri, 18 Jul 2008 03:01:40 +0000, Larry wrote:

Herodotus wrote in
m:

http://www.isotherm.com/en/product?f...1254FirefoxHTM
LShellOpenCommand

I've got a fridge in my truck about the size of a Cruise 85 running off the
shop inverter. It's made in Korea and cost $US89 from Home Depot on sale
in January of '06. What attracted me was the can dispensing rack in the
door. Has a tiny freezer that's near worthless but could keep some meat
solid. Ice trays freeze really fast.

What the hell makes a BOAT fridge the same size cost 10 times the price,
the $60 inverter screwed into the case?

What a rip.....boat crap!

Stop by. I have another one in the house....holding the Heineken's minikeg
to just the right temperature, right next to the computer desk....(c;

Larry, Larry, you just don;t understand. You see cheap Korean fridges
are sold by some bloke at Home Depot while proper YACHTING gear is
sold by gentlemen wearing white pants and those funny shoes with all
the squiggly cuts in the soles.

Obviously anything sold by a white pants salesman has got to be the
correct type of thing that a fellow would want on his boat whereas one
would rather be dead then to have the chaps know that he had a (Ug!)
Home Depot device aboard.

Besides, we were talking about built in fridges :-)

Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

Larry, Bruce,

Gentlemen (My God! I have to lie sometimes to get what i want)

It does seem to me to be a lot of money to pay for the systems that
are sold. The problem is that I have a great wind generator (another
that can be added if necessary) an 80 watt solar panel (and will get
another) as well as a smart charge system for my 120 AMP alternator.

I have 4 Trojan 6 volt batteries in parallel and series - 440 Amp
hours. If necessary I could get another 2 of these but at the moment
don't think I need them.

I really want a system that will work well with minimal charging of
`the batteries by the alternator. I don't want one that I have to run
the motor for an hour each day just to run a fridge. I have noticed
that often the wind generator tops up the batteries and then feathers.
I hate to see potential charging going to waste especially if the wind
and sun fizzle out later in the day.

Well, first of all you need a "Larry Lesson" on how batteries charge
as your 110 amp alternator is just a waste of money.

Secondly, I have three 42.7 watt, old, solar panels and, God willing
the sun shines every day, they will keep MY 440 AH battery bank
charged and run my old 12 volt built in fridge. (providing I don't
turn on a light very often).

If you are going to hang about in Oz you may have enough wind to make
your wind generator useful but if you move up to Pinang they don't
work as well :-) Apparently they become indolent once they arrive in
Malaysia.

Now, there is a guy down the jetty that I just talked to, has a new
eutectic, built in, powered by a 12/220 volt compressor and tells me
that if the fridge is operated correctly (runs all the time; keep ice
on the plate; keep the fridge full; etc.) he gets buy with two solar
panels. I will get some details, panels, fridge model, etc., and let
you know as it sounds like what you want.

I am normally seldom moored to a dock and thus shore electricity is
not a factor. (BTW Herodotus isn't tethered either - in case either of
you make a smart arsed comment regarding my English useage).

What smartass? Moored - "hitched to a dock" We usually say "tied up"
where I come from, though.

The idea of a holding plate is that I could utilise periods of greater
charge whereas a conventional fridge runs off and on over the entire
day.

I do wonder why these systems are so expensive though. I can think of
a lot of things I could do with the dollars.

Now, now. To quote John D. Rockefeller, "If you have to ask how much
you can't afford one" :-)

Do you know if I can just buy the components separately or is there
something wrong with my logic?

If you get into seriously thinking of building a system I can probably
pick Stephan's brains for what, where and how much. It probably
wouldn't be cost effective to have him build the system as he is
oriented toward the high end of the market but he is a pretty friendly
guy and would probably tell me where he gets parts.

If you are thinking of building your own system beg, borrow or steal a
copy of the book by Nigal Calder "Refrigeration for Pleasure Boats:
Installation, Maintenance and Repair" as it has all the calculations
to plan insulation thickness, plate size, heat exchanger specs -
everything you wanted to know and more. Well worth the price.

BTW Bruce, I am due in KL on next Thursday night Inshahallah. Are you
still at Phuket? Apart from Penang, I am also visiting KL (Pelabuhan
Klang), Johor Baru, Singapore and Karimun and Medan in Sumatera. I
would love to make time to meet with you If I can. Don't worry. I
shall speak and listen slowly and can understand dull, boring, tedious
Southern drawl if required.

Can't make it this trip. I'm just out of the Yard and haven't even
been able to scrape the yard dirt off because it has been raining so
hard. As soon as I get that done I'm off to Bangkok for a couple of
weeks to my wife.

Have to be next trip.

I do appreciate both of your advice and your help.

regards
Peter

Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

Advice on refridgeration unit please

On Fri, 18 Jul 2008 15:44:05 +0000, Larry wrote:

Bruce in Bangkok wrote in
:

Don;t know what happened but I see I sent several copies of the same
message. My apologies to all for the excess bandwidth taken.

Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

Serves ya right.....Larry Lesson indeed!

Shorthand, old chap.

Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

Advice on refridgeration unit please

On Fri, 18 Jul 2008 10:21:49 -0400, Ryk
wrote:

On Fri, 18 Jul 2008 10:29:29 +1000, in message

Herodotus wrote:

I have spent a considerable amount of time researching its replacement
and am considering the Isotherm ASU 3751 with the self pumping heat
exchanger around the galley through hull. I assume that the inside air
temperature of the boat would exclude an air cooled (cheaper and no
plumbing and no possibility of corrosion of the special sea cock).

I installed an air cooled Isotherm ASU 3 years ago and have been very
happy with the performance. I thought about the self pumping heat
exchanger but decided I didn't need it on the Great Lakes. The power
consumption seems to be about 15 amp hours per day on 25C days, but
that will vary enormously with installation specifics.

I would be inclined to believe their recommendations for the self pump
in tropical applications, although you might ask about the potential
for an upgrade. The basic units are the same, so you might be able to
try the air cooled version and move to the self pump water cooled if
needed.

The ASU feature seems to save a lot by running full out when the
engine is on, but I have no measurements to prove it.

As an engineer I think the self pump design is very elegant, and am
inclined to install one just for that reason.

Ryk

Hi Ryk,
Thanks for this as I don't know how real the company's power usage
figures are and at what outside temperature they are quoted for.

I note that the one I am looking at states that it is for a
refridgerator, not a freezer. However an optional extra is an ice
making tray. Does this mean that one could have a small freezer
compartment overflowing to a larger fridge one. A freezer would be
great but not vital. Iced water would be nice though.

cheers
Peter

Advice on refridgeration unit please

On Jul 18, 4:46*pm, Bruce in Bangkok
...
In practice high output alternators make a big difference getting up
to about 80% charge. *That can be very, very useful. *It may be that
you have some logic and battery chemistry in your text books but I
live on my boat and go voyaging a bit. *High output alternators are a
good thing.

So do Larry, Peter and myself. (Well, larry doesn't live on one, he
just voyages).

Frankly, in my experience a 110 amp alternator and a 440 A.H. battery
bank is overkill,
...

Well, I've got two 110 amp alternators on a 510 AH bank and I think
that's about right. My experience is that I can bulk my batteries
quickly with my 110's. Sometimes I top them off with solar and
sometimes I work them in the 80%-50% range. Every week or so they get
a full charge and that does take a long time, but still less time than
it would with a 60 amp unit. YMMV.

-- Tom.

Advice on refridgeration unit please

Ryk wrote in
:

The exterior of a typical little bar fridge is a heat dissipation
surface, so insulating it from the surroundings would be a bad idea.

Ryk

You are correct for the new ones.

I was cruising on of my thrift shops today and paid $10 for a Sears
Kenmore 2.2 cu ft little bar fridge in nice condition. "I don't think
it runs.", the check out guy said. "The compressor doesn't run."

Well, always skeptical, I plugged it into one of the test outlets on the
shelf and fired it up. The evaporator froze my skin to the aluminum
evaporator in about 3 minutes from a dead start. I turned it around
because I couldn't hear it running, either! The little compressor is SO
quiet you can't even hear it start!

Looking at the various labels I saw it was running R-12, which would
account for its quiet operation at such low pressure. Then, I spotted
the CURRENT DRAIN at 120VAC of .6A! Hmm...72 watts running = 5.2A at
13.8V on charged house batteries through a little high efficiency
inverter...exactly what's on the thousand dollar marine fridges.
Getting it home, I confirmed 71 watts under full head pressure and the
hole external condensor sticking out the back of it....NOT HEATING THE
DAMNED CASE to go back through the insulation, got hotter than hell...a
great heat transfer was taking place!

It's sitting on the floor next to the printer, tonight, testing. The
wattmeter still sits on 71W when it's running, which I take to be about
15% duty cycle on my stopwatch after the initial cooldown and
temperature stabilization to 38F on the top shelf away from the evap.
The thermometer inside the little box evap sits on 8F at about 2/3
thermostat setting and should keep the icecream hard...(c;

There's two can/bottle racks with a holding bar in the door, which is
not damaged like my other R12 fridge (much older). None of the plastic
is cracked anywhere. I assume this means it spent ZERO time in a
college dorm full of Bud.

I'll clean it up tomorrow and swap it for the 4cuft currently in my
stepvan. That one runs R-134a and draws nearly 130 watts after it
stabilizes...reducing my AH drain to half with still plenty of room to
keep the colas and sandwiches cold on the Honda or inverter off the
house batteries (330AH golf cart beasts.)

I'm also going to see....I think the nice door on this fridge will fit
on my favorite old R-12 fridge, the one with the 40 watt vibrator
compressor from Sweden. That's the most efficient little fridge I own
but its door has gotten so leaky and hard to keep closed I gave up and
set it aside. This nice oak-grained Kenmore door will restore it to its
former glory. THAT fridge will run off a 75 watt inverter that is built
into a cigarette lighter plug! 40 watts = less than 3A drain off
13.8VDC, but I'm going to compare the AH drain over 4 hours between
these R-12 units. The compressor model may be more efficient than the
vibrator compressor, leading the new fridge to win the AH
Contest....from lower runtimes than the vibrator runs.

I'll be in the lab with my Linux tablet running spreadsheets if Algore
calls for advise....

Advice on refridgeration unit please

Ryk wrote in
:

You would be much better off filling the freezer with a phase change
fluid that melts/freezes somewhere in the desired temperature range.
Water, for instance...

I have lots of freeze packets, both in plastic bags and hard plastic cooler
packs made to go between the cans. I'll try them, too, as a cold plate.

Advice on refridgeration unit please

" wrote in news:8efb7662-ce61-
:

But, what you really want is a diesel plug in
hybrid...

Not with a $3000 to $6000 "battery pack" in them I don't. Drop by your
Prius dealer, back in the parts department, and tell them your Prius got
in a crash (no battery warranty excuse) and ask 'em how much a new high
voltage battery pack for a 2-year-old Prius will cost you.....

You cannot save money in a hybrid with $6000 parts to buy!

.....and it won't run without it!

http://www.cleangreencar.co.nz/page/prius-battery-pack

To get 150mpg in a Prius, they have a $US9,500 battery pack to install
turning it into nearly an electric car:
http://www.engadget.com/2007/10/20/b...ade-for-prius-
claims-150mpg/

I'm also interested in enclosed motorcycles, which this one isn't
really:
http://www.engadget.com/2008/06/28/t...30-pound-huvo-
electric-car/
......and this one is.....
http://www.engadget.com/2008/06/22/e...motorcycle-is-
green-and-ghastly/

An enclosed motorcycle makes a lot of sense because it completely
bypasses the stupid nanny regulations the oil companies have used for
years to keep micro-sized vehicles Europeans and Asians drive OFF THE US
ROADS, saving millions of dollars in gas guzzler fuel costs.

Why I can ride this:
http://powersports.honda.com/scooters/model.asp?
ModelName=Reflex&ModelYear=2007&ModelId=NSS2507
made of plastic with a metal frame inside it and NO SAFETY EQUIPMENT is
permitted by the ruling class, but I cannot drive this:
http://wheels.blogs.nytimes.com/2008...no-the-worlds-
cheapest-car/
which only costs $2500 and gets nearly as much mileage as the
scooter....is just STUPID!

Microcars need to be classed as motorcycles, whether oil company
executives like Cheney and Bush like it or not. It should be a personal
decision whether I want to drive one and risk my life....EXACTLY as it
is with my Honda Reflex getting 76mpg driving easy and 65mpg driving it
like I stole it...(c;

I'm not even forced to wear a helmet in SC after 12,000 noisy
motorcycles kept circling the State House back in the 70's to have that
stupidity recinded. I was riding a Honda CB750 4-cylinder motorcycle in
that parade, I'm proud to say. Thousands of motorcyclists DIDN'T die to
fulfill the safety bureaucrats worst nightmare.

I do wear a helmet, without exception. That should be MY decision, not
some highway department bureaucrat or lawyer politician.....

Would you drive a Nano for $2500 that gets 70 mpg?

Advice on refridgeration unit please

Bruce in Bangkok wrote in
:

Frankly, in my experience a 110 amp alternator and a 440 A.H. battery
bank is overkill,

The only time it wouldn't be is if you have some heavy loads running while
trying to recharge, like a big fridge trying to freeze a coldplate off
12VDC or running the microwave off the inverter while the diesel is
running, etc.

110A at 14V is only 1540 watts and the microwave would eat a thousand of
that. A big inverter loaded down can consume the whole 110A output, frying
the intermittent duty alternator if that's what it is, and most of them are
I found out with Skip's purchase here.

Until the charging current drops off the amount you want to use, and only
if the alternator is continuous or "heavy duty" rated, can you run loads
off it of any amount.....

Advice on refridgeration unit please