"Skip Gundlach" wrote in message
ups.com...
We look at our filter for water movement. If it's coming in, it's
going out. More reliable than trying to stick our heads out to see
whether there was a splash, in any event, and much quicker as it's
right next to where the key is...

We thought about relocating the exhaust, but got talked out of it for
a variety of reasons. On our next extended haul we'll revisit doing
it out the transom rather than low on the stern side as it is now...

Wilbur, I don't know his system, but another's I know of uses a direct
drive 1HP motor to chill cold plates. Very high amps, relatively short
time. My estimated (see my upcoming electrical budget and scenaios)
use is over an entire day, but is more like 35-40AH.and uses, when
running full blast, as approximately yours does, 4.7A..

L8R

Skip


Skip, it could also be coming in and going into your bilge. Also, having the
exhaust under water makes it more likely for water to back up into your
exhaust system in following seas. Free and clear of the water is for sure
the better way to go.

"KLC Lewis" wrote:

"Skip Gundlach" wrote in message
oups.com...
We look at our filter for water movement. If it's coming in, it's
going out. More reliable than trying to stick our heads out to see
whether there was a splash, in any event, and much quicker as it's
right next to where the key is...

Bob always walks back to see if exhaust is coming out, even if
everything sounds all right from the cockpit. I don't think much of
your method.

We thought about relocating the exhaust, but got talked out of it for
a variety of reasons. On our next extended haul we'll revisit doing
it out the transom rather than low on the stern side as it is now...

Wilbur, I don't know his system, but another's I know of uses a direct
drive 1HP motor to chill cold plates. Very high amps, relatively short
time. My estimated (see my upcoming electrical budget and scenaios)
use is over an entire day, but is more like 35-40AH.and uses, when
running full blast, as approximately yours does, 4.7A..

Skip, it could also be coming in and going into your bilge. Also, having the
exhaust under water makes it more likely for water to back up into your
exhaust system in following seas. Free and clear of the water is for sure
the better way to go.

I agree - we have a high loop which goes up into the cockpit to keep
waves from coming into the engine through the exhaust, and an
anti-siphon break on the cooling system.

I don't know what our refrigeration system uses when it is hooked up
to dock power. When we are not hooked up, we run the engine driven
system for 45 minutes twice a day. The frig is not attached to the
batteries. We have 19 cu ft of frig - 1/3rd freezer. It will not
freeze ice cubes or keep ice cream, but it will keep meat frozen, and
is perfectly adequate for our needs. Actually it is rather too big
for us, but that's what came with the boat.

On Fri, 10 Aug 2007 18:29:15 -0400, Jeff wrote:

the
fridge, radar, and autopilot must be turned off if the engine is
running and the batteries are not fully charged?

Of course not. It is important however to get the batteries back up
to at least the 80 or 90% level in a reasonable length of time. If
the alternator belts are slipping/burning at less than the 100 amp
level, something is wrong, probably belt tension or belt type. Over
100 amps dual belts are generally necessary.

On Fri, 10 Aug 2007 18:46:36 -0400, "Wilbur Hubbard"
wrote:

I must inform you if your fridge draws 30 amps at 13VDC then there's
something seriously wrong with it. Mine only draws 5 amps. Hell, you
could run an air conditioner on 30 amps.

Probably cooling holding plates with a high powered condensing unit.
That's what I do, works fine, 3/4 hp compressor, 4 hours per day, 9
amps AC, 90 amps DC.

* Wayne.B wrote, On 8/11/2007 12:12 AM:
On Fri, 10 Aug 2007 18:46:36 -0400, "Wilbur Hubbard"
wrote:

I must inform you if your fridge draws 30 amps at 13VDC then there's
something seriously wrong with it. Mine only draws 5 amps. Hell, you
could run an air conditioner on 30 amps.

Probably cooling holding plates with a high powered condensing unit.
That's what I do, works fine, 3/4 hp compressor, 4 hours per day, 9
amps AC, 90 amps DC.

That seems odd - my 1/2 motor, a Leeson, is rated at 1/2 Hp, with a 39
Amp draw. It normally uses no more than 30 Amps. Scaling up, I would
expect yours to be 60 Amps or less.

* Wayne.B wrote, On 8/11/2007 12:08 AM:
On Fri, 10 Aug 2007 18:29:15 -0400, Jeff wrote:

the
fridge, radar, and autopilot must be turned off if the engine is
running and the batteries are not fully charged?

Of course not. It is important however to get the batteries back up
to at least the 80 or 90% level in a reasonable length of time.

But you can run a lot of stuff tapping power off a 100 Amp alternator
and still leave it with a lot of charging power. In my case, the 30
Amp fridge, the TV, computer, and all the instruments don't come up to
50 Amps. My point with the fridge is that it going to use the power
at some time during the day, its more efficient to do it directly off
the charge source.

If
the alternator belts are slipping/burning at less than the 100 amp
level, something is wrong, probably belt tension or belt type. Over
100 amps dual belts are generally necessary.

Alignment is a common cause - being off 1/8 inch will kill a belt in
no time. Also, a faulty regulator that's "spiking" the field voltage
can do it.

* Wilbur Hubbard wrote, On 8/10/2007 9:15 PM:
....
However, a 30 Amp draw is quite common for my type of fridge. Its a
1/2 HP motor driving a compressor that feeds several holding plates in
a 9 cu ft fridge and 5 cu ft deep freeze. The actual load varies from
20 to 35 Amps. Here in Maine I've been monitoring it carefully, and
it has taken about 40 Amp-hours per day for the last two weeks. The
fridge stays at 42-46 degrees, the freezer at 15-20, both measured at
the top shelf.

What you're doing is pretty wasteful.

It was installed before the current high efficiency Danfoss unit were
available. However, it still seems more efficient than yours.

Sounds like you have a separate
freezer and refigerator. That's dumb. All you need is a freezer that
connects to your fridge box with a well-insulated duct. Keep your
freezer full of meats and other dense stuff and run it all the time.
Allow some of the excess cold air to migrate into your fridge box by
controlling the size of the duct. The duct should run from the top of
your freezer box to the bottom of your fridge box. If you do this, you
could run the entire system on one modern, efficient Danfoss compressor.

Spill-over systems have some virtue. However, that requires a
particular geometry that can't always be achieved. Also, its rather
doubtful that one Danfoss could chill a system as large as mine. Even
if it could, I would still split it into two. There's a huge
advantage to having redundancy and being able to scale down so a boat
could be left unattended for moderate periods.

Holding plates are a stupid system because they are bulky and take up
too much room inside the ice box.

They take no space at all; their volume is not included!

Better to have a flat or box-shaped
evaporator and use meats and other dense frozen foods as the holding
plate. What I do is completely fill the freezer part with canned beer.
The Ice beer works best because of the high alcohol content it doesn't
freeze and bust open. But, the thermostat cant' be set to the cold
position. About 1/4 the way to all the way cold works best. My freezer
contains 15 twelve ounce beers.

That's a pretty small freezer.

I relpace them one at a time as I drink them. I maybe drink six on a
hot day. I cycle new beers from the fridge
section to the freezer section and add new ones to the fridge section as
I drink them. An admirable holding plate.

In other words, you open the freezer at least six times a day? And
your antifreeze consumption certainly explains the quality of your posts!


My box is very-well insulated and because of it my compressor usually
runs 20 minutes on 40 off in the summer and about 15 minutes on and
close to an hour off in the cooler months of winter. Let's call that
one-third of 24 hours for 8 hours total or 40 amp hours. The box
measures about 1.5 feet by 2 feet by 1.5 feet. For about 4.5 feet cubed.

That's about a third the size of mine combined boxes, which also is
using 40 Amp-hours a day. And the warmest spot in my freezer is 20
degrees. Even in the tropics, serving three people, we rarely went
over 90 Ah a day. And that was before I learned how to maintain it
myself.

It and everything else is run by two Evergreen 100 watt photovoltaic
arrays connected to a Sunsie charge controller. The fridge runs more in
the summer months but the days are longer too so the batteries stay
well-charged the year around.

Adding more solar is high on my priority list.

... If you have the room, one
foot of insulation all around is the way to go.

My freezer has 7 inches all around, including the top. This biggest
issue now is that the seals have degraded, so they now let in too much
humidity. The fridge insulation is more important as you move south
and have higher temperature differentials, and hot nights. My fridge
alone can get by on as little as 15 Ah a day when a cold front comes
through!

On Sat, 11 Aug 2007 06:57:27 -0400, Jeff wrote:

Probably cooling holding plates with a high powered condensing unit.
That's what I do, works fine, 3/4 hp compressor, 4 hours per day, 9
amps AC, 90 amps DC.

That seems odd - my 1/2 motor, a Leeson, is rated at 1/2 Hp, with a 39
Amp draw. It normally uses no more than 30 Amps. Scaling up, I would
expect yours to be 60 Amps or less.

I'm going through an inverter in DC mode, probably losing something
there. The compressor itself is AC only.

"Jeff" wrote in message ...
Oddly, you're always claiming that charging a 450 Ah bank at 80 or 90 Amps
is doing great damage. What I'm doing is reduces that to 50 Amps
charging, with 30 Amps to the fridge. Are you claiming that the fridge,
radar, and autopilot must be turned off if the engine is running and the
batteries are not fully charged?

Jeff, it sounds like you are mixing Amps and Amp-hours. I'm sure you know
the difference, but it does make things confusing. For example, my refrig
draws about 5A when running, which it does perhaps 6 hours a day in the
tropics. This gives a 24-hour consumption of 30 Ah (at 12V).

-Paul
-S/V VALIS

On Sat, 11 Aug 2007 09:47:02 -0700, "Paul" wrote:

Jeff, it sounds like you are mixing Amps and Amp-hours. I'm sure you know
the difference, but it does make things confusing. For example, my refrig
draws about 5A when running, which it does perhaps 6 hours a day in the
tropics. This gives a 24-hour consumption of 30 Ah (at 12V).

That sounds incredibly efficient. What size box do you have and what
kind of system? Holding plates? Compressor type?