Hi,

I need to replace my existing Tropicool eutectic refridgerator which,
as it is dependent on the ambient air temperature, is just no good for
the tropics. Quite often, the water temperature around South East Asia
and Northern Australia reaches at least 30 degrees Celsius (86 F) and
then some.

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).

From Defender, at $1,900 it is about $1,000 cheaper than the
Technautics one. As they seem to use the same basic compressor and
both have ASU (automatic sensing of state of charge of the electrical
system) I imagine that the only difference would be the amount of coil
surface in the holding plates.

http://www.isotherm.com/en/product?f...l OpenCommand

Any thoughts, ideas, experience etc would be gratefully received.

I know that there was a thread on refridgeration earlier but I cannot
find it. I recall an excellent article by a M Kohlmann (sp???)

regards
Peter

On Fri, 18 Jul 2008 10:29:29 +1000, Herodotus
wrote:

Hi,

I need to replace my existing Tropicool eutectic refridgerator which,
as it is dependent on the ambient air temperature, is just no good for
the tropics. Quite often, the water temperature around South East Asia
and Northern Australia reaches at least 30 degrees Celsius (86 F) and
then some.

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).

From Defender, at $1,900 it is about $1,000 cheaper than the
Technautics one. As they seem to use the same basic compressor and
both have ASU (automatic sensing of state of charge of the electrical
system) I imagine that the only difference would be the amount of coil
surface in the holding plates.

http://www.isotherm.com/en/product?f...l OpenCommand

Any thoughts, ideas, experience etc would be gratefully received.

I know that there was a thread on refridgeration earlier but I cannot
find it. I recall an excellent article by a M Kohlmann (sp???)

regards
Peter


A while ago I talked to Stephan, our local refrigeration expert, who
recommends having a look at the new variable speed compressor units.
He used to build and recommend eutectic installations but says that
the new 12 Volt compressors use so little electricity that he now
recommends them.

Temperature - I have a 12 volt, air cooled condenser, unit with
the condenser mounted under the cockpit floor. It has worked for the
past 15 years with no problems.

If you really, really, can't find any good information on the variable
speed units let me know and I'll take a drive down to Stephan's place
and get you more info.

As I'm sure you are aware, a real sailor will eat nothing but salt
junk and ship's biscuit. None of this namby-pamby refrigerated stuff
for he man, AND, since you don't drink beer you have even less need
for a fridge then usual.


Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

On Fri, 18 Jul 2008 07:45:40 +0700, Bruce in Bangkok
wrote:



A while ago I talked to Stephan, our local refrigeration expert, who
recommends having a look at the new variable speed compressor units.
He used to build and recommend eutectic installations but says that
the new 12 Volt compressors use so little electricity that he now
recommends them.

Temperature - I have a 12 volt, air cooled condenser, unit with
the condenser mounted under the cockpit floor. It has worked for the
past 15 years with no problems.

If you really, really, can't find any good information on the variable
speed units let me know and I'll take a drive down to Stephan's place
and get you more info.

As I'm sure you are aware, a real sailor will eat nothing but salt
junk and ship's biscuit. None of this namby-pamby refrigerated stuff
for he man, AND, since you don't drink beer you have even less need
for a fridge then usual.


Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

Thanks Bruce,

I do believe that the variable speed compressor your local man refers
to is the same type of thing as an ASU which both Technautics and
Isotherm use. When the unit senses charging voltage it speeds up the
compressor to freeze the holding plate asap. When the charging current
goes - such as when the alternator on the engine shuts off, it senses
the battery charge and turns away much slower.

Now I do know that, like your non-friend with the little appendage, I
should be eating hard tack ship's biscuits and bully beef. However,
the biscuits usually contain weevils which is why the old salts banged
them on the table in an attempt to dislodge them. Having eaten a
variety of new things in my life I am not averse to eating said
weevils but am unsure if they are halal. I do like corned beef though.
It is one of my favourite foods, especially in a fresh bread sandwich
with sliced onions so I suppose that I am partially a sailor. I refuse
point blank to use a wooden bucket though but have been known to squat
in the small, square hanging-over-the-stern opened bottom toilets on
Indonesian trading boats.

Question. Does your air cooled unit work much more in the tropics than
it did in more temperate climes?

I would much prefer an air cooled system which, apart from being
cheaper, does not have the complication of possible electrolysis.

I seem to recall somewhere that you don't need a huge airflow for the
modern air cooled ones.

cheers
Peter

On Fri, 18 Jul 2008 12:00:29 +1000, Herodotus
wrote:

On Fri, 18 Jul 2008 07:45:40 +0700, Bruce in Bangkok
wrote:



A while ago I talked to Stephan, our local refrigeration expert, who
recommends having a look at the new variable speed compressor units.
He used to build and recommend eutectic installations but says that
the new 12 Volt compressors use so little electricity that he now
recommends them.

Temperature - I have a 12 volt, air cooled condenser, unit with
the condenser mounted under the cockpit floor. It has worked for the
past 15 years with no problems.

If you really, really, can't find any good information on the variable
speed units let me know and I'll take a drive down to Stephan's place
and get you more info.

As I'm sure you are aware, a real sailor will eat nothing but salt
junk and ship's biscuit. None of this namby-pamby refrigerated stuff
for he man, AND, since you don't drink beer you have even less need
for a fridge then usual.


Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

Thanks Bruce,

I do believe that the variable speed compressor your local man refers
to is the same type of thing as an ASU which both Technautics and
Isotherm use. When the unit senses charging voltage it speeds up the
compressor to freeze the holding plate asap. When the charging current
goes - such as when the alternator on the engine shuts off, it senses
the battery charge and turns away much slower.

The conversation was very general but I was left with the impression
that Stephan was talking about a conventional fridge, not a cold
plate. As I understood it the compressor initially ran at full speed
but slowed as the temperature decreased or the pressure built up????

We were mainly discussing my conventional fridge and he was saying
that the new ones drew much less electricity.

Now I do know that, like your non-friend with the little appendage, I
should be eating hard tack ship's biscuits and bully beef. However,
the biscuits usually contain weevils which is why the old salts banged
them on the table in an attempt to dislodge them.

Wichity (spelling?) grubs?

Salt junk is pieces of beef thrown in a barrel of brine. When you want
to eat it you first need to soak it in fresh water for a while. Sort
of like salt fish, Ikan Garam?

Having eaten a
variety of new things in my life I am not averse to eating said
weevils but am unsure if they are halal. I do like corned beef though.
It is one of my favourite foods, especially in a fresh bread sandwich
with sliced onions so I suppose that I am partially a sailor. I refuse
point blank to use a wooden bucket though but have been known to squat
in the small, square hanging-over-the-stern opened bottom toilets on
Indonesian trading boats.

I was down in Irian Jaya and say a really nice, apparently, ex navy
powerboat. about 40 ft. that looked like it had decent size quarters
on it. Built out over the stern was an added on "head". A one metre
by one metre building, with a roof and door. Looked quite comfortable.


Question. Does your air cooled unit work much more in the tropics than
it did in more temperate climes?

I installed this one in Singapore after the old one died of corrosion.
My very old solar panels run it as long as the sun shines every day.

I would much prefer an air cooled system which, apart from being
cheaper, does not have the complication of possible electrolysis.

I seem to recall somewhere that you don't need a huge airflow for the
modern air cooled ones.

The condenser on mine is about 8-10 inches square and has a 12 volt
"muffin" fan to cool it.

cheers
Peter

Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

Herodotus wrote in
:

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;

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

Herodotus wrote in
:

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)

Bruce in Bangkok wrote in
:

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.



Oh, I see....(c;

I'm trying my best to buy a new Smart CDi diesel car to replace my aging
fleet of old Mercedes diesels, and still maintain my energy independence
with another diesel. They don't import them into the USA because the
President and his cronies are all oil company executives who puke when
someone tries to import a car that uses 3.3 litres/100km and has the lowest
carbon footprint on the planet, including electric cars if you consider
power plant emissions.

The arrogant *******s at the local Smart Dealer, Baker Motors, didn't like
me parking my old stepvan out front or my wearing T-shirt/blue jeans into
the showroom that has NO SMART CARS FOR SALE!

I laid out $15,000 in $100 bills fanned them out on the desk and said, "I'd
like a Smart For 2 CDi with just an air conditioner installed, please."

NO GO. They would make me a deal on a new Maybach they're stuck with, now
that Maybach is going out of production, however....(c;

I bundled my cash back up but they did take my name and number...finally.

Noone wants to sell me a new car! I can't believe it!

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.

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).

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.

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

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.

I do appreciate both of your advice and your help.

regards
Peter

On Fri, 18 Jul 2008 05:24:04 +0000, Larry wrote:

Bruce in Bangkok wrote in
:

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.



Oh, I see....(c;

I'm trying my best to buy a new Smart CDi diesel car to replace my aging
fleet of old Mercedes diesels, and still maintain my energy independence
with another diesel. They don't import them into the USA because the
President and his cronies are all oil company executives who puke when
someone tries to import a car that uses 3.3 litres/100km and has the lowest
carbon footprint on the planet, including electric cars if you consider
power plant emissions.

The arrogant *******s at the local Smart Dealer, Baker Motors, didn't like
me parking my old stepvan out front or my wearing T-shirt/blue jeans into
the showroom that has NO SMART CARS FOR SALE!

I laid out $15,000 in $100 bills fanned them out on the desk and said, "I'd
like a Smart For 2 CDi with just an air conditioner installed, please."

NO GO. They would make me a deal on a new Maybach they're stuck with, now
that Maybach is going out of production, however....(c;

I bundled my cash back up but they did take my name and number...finally.

Noone wants to sell me a new car! I can't believe it!


I suppose I'm out of touch but what is a "Smart CDi diesel car"? A
maker called "Smart" or does that refer to the engine controls?

I ask as all the newer diesel pickups made in Thailand have computer
controlled injection these days.


Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

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
:

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)