copper tubing and sea/salt water

On Tue, 15 Aug 2006 23:59:11 GMT, "MarshallE" <meakes.DeleteThis@triad.rr.com>
wrote:

>Hi,
>
>What is the normal metal tubing used for keel coolers and how long should it
>last?
>
>I am having a heck of a time locating a seawater condenser and have about
>decided to make from scratch.
>
>I want to A/C using 5 tons for my boat.
>
>thanks for help and opinions,
>
>Marshall


Wow! Some boat!: 5 ton AC units are used in 2000 sq ft houses.
That could be a 100 ft long stateroom that's 20 ft wide then?



Brian Whatcott Altus OK
 >> Stay informed about: copper tubing and sea/salt water 

You should use a copper based stainless steel. The alloy is commonly used
for heat exchangers and oil coolers on large commercial marine engines. It
goes by several names, but I think cunifer(sp) is one of them. Be careful
with your construction and avoid exposing it to unsupported vibration as it
is prone to fatigue cracking. However, it is very resistant to salt water
corrosion.
Steve

"MarshallE" <meakes RemoveThis @triad.rr.com> wrote in message
news:jdtEg.34926$so3.22800@southeast.rr.com...
> Hi,
>
> What is the normal metal tubing used for keel coolers and how long should
> it
> last?
>
> I am having a heck of a time locating a seawater condenser and have about
> decided to make from scratch.
>
> I want to A/C using 5 tons for my boat.
>
> thanks for help and opinions,
>
> Marshall
>
>
 >> Stay informed about: copper tubing and sea/salt water 

Thanks and one more question.

Is there a formula for calculating how much copper tubing and size is
needed for handling my 5 ton AC unit. I am wondering if a 100 ft. coil of
1/2" refrigeration tubing for the freon and either shroud the copper tube
with larger plastic tubing for sea water to travel or simply submerge the
copper coil in a large drum with sea water circulating/exchanging. Avg. sea
temps range from 40 to 85 degrees F.

Many thanks for help.

Marshall
"Steve Lusardi" <stevenospam.TakeThisOut@lusardi.de> wrote in message
news:ebtpr6$olg$02$1@news.t-online.com...
> You should use a copper based stainless steel. The alloy is commonly used
> for heat exchangers and oil coolers on large commercial marine engines. It
> goes by several names, but I think cunifer(sp) is one of them. Be careful
> with your construction and avoid exposing it to unsupported vibration as
it
> is prone to fatigue cracking. However, it is very resistant to salt water
> corrosion.
> Steve
>
> "MarshallE" <meakes.TakeThisOut@triad.rr.com> wrote in message
> news:jdtEg.34926$so3.22800@southeast.rr.com...
> > Hi,
> >
> > What is the normal metal tubing used for keel coolers and how long
should
> > it
> > last?
> >
> > I am having a heck of a time locating a seawater condenser and have
about
> > decided to make from scratch.
> >
> > I want to A/C using 5 tons for my boat.
> >
> > thanks for help and opinions,
> >
> > Marshall
> >
> >
>
>
 >> Stay informed about: copper tubing and sea/salt water 

I gotta ask, with water temps like you mention, are you in Corpus
Christi Bay?

MarshallE wrote:
> My boat is a 1942 Wheeler 83 ft. long. She is one of the few remaining
> cutters used in WWII and participated at Normandy.
>
> I am thinking about using a high pressure residential air handler/evaporator
> made by Unico. My goal is to run 2" PVC pipe for the duct wrapped with foam
> rubber insulation.
>
> I am hoping that there is a heat/cool transfer engineer that can help with
> the research.
>
> Marshall
>
> "Glenn Ashmore" <gashmore DeleteThis @cox.net> wrote in message
> news:VDxEg.10485$ok5.2712@dukeread01...
> > Try Alaska Copper
> > http://www.alaskancopper.com/cuni/pdf/9010_seamless_tubing.pdf They have
> a
> > 90/10 copper/nickel tube that is probably the best material for exposed
> > condensers.
> >
> > You need to do a lot of research to roll your own A/C condenser. The tube
> > size and length is a compromise between pressure drop, heat transfer and
> oil
> > movement. The surface area has to be sufficient to transfer enough heat.
> > If it is to long and small diameter the pressure drop will be to high. If
> > it is short and large diameter the refrigerant moves to slow so the oil
> will
> > drop out and be trapped in the condenser which will starve the compressor
> of
> > lubrication.
> >
> > --
> > Glenn Ashmore
> >
> > I'm building a 45' cutter in strip/composite. Watch my progress (or lack
> > there of) at: http://www.rutuonline.com
> > Shameless Commercial Division: http://www.spade-anchor-us.com
> >
> > "MarshallE" <meakes DeleteThis @triad.rr.com> wrote in message
> > news:jdtEg.34926$so3.22800@southeast.rr.com...
> > > Hi,
> > >
> > > What is the normal metal tubing used for keel coolers and how long
> should
> > > it
> > > last?
> > >
> > > I am having a heck of a time locating a seawater condenser and have
> about
> > > decided to make from scratch.
> > >
> > > I want to A/C using 5 tons for my boat.
> > >
> > > thanks for help and opinions,
> > >
> > > Marshall
> > >
> > >
> >
> >
 >> Stay informed about: copper tubing and sea/salt water 

MarshallE wrote:
> Hi,
>
> What is the normal metal tubing used for keel coolers and how long should it
> last?
>
> I am having a heck of a time locating a seawater condenser and have about
> decided to make from scratch.
>
> I want to A/C using 5 tons for my boat.
>
> thanks for help and opinions,
>
> Marshall


I don't think you can manufacture a Keel Cooler condenser for a five
ton air conditioning unit that will be as good as the one you could
buy. Keel coolers are commonly used on boats larger than 50 feet. When
refrigeration or A/C systems use water as a condenser heat removal
medium an extra device is needed in refrigerant circuit to control
temperature of low side pressure gas . I would inform Unico of your
intensions on water cooling their unit, so they can add a hot gas
bypass valve if it is to be cooled by a keel cooler. If you plan on a
pumped water cooled condenser then you can add a water temperature
regulating valve to condenser water line.

The size of any type of condenser is based on system tonnage.
Seawater condensers are available from most A/C and refrigeration
suppliers like United Refrigeration.
For keel coolers there are several companies that advertise in Trade A
Boat or National Fisherman magazine.
 >> Stay informed about: copper tubing and sea/salt water 

My boat is a 1942 Wheeler 83 ft. long. She is one of the few remaining
cutters used in WWII and participated at Normandy.

I am thinking about using a high pressure residential air handler/evaporator
made by Unico. My goal is to run 2" PVC pipe for the duct wrapped with foam
rubber insulation.

I am hoping that there is a heat/cool transfer engineer that can help with
the research.

Marshall

"Glenn Ashmore" <gashmore DeleteThis @cox.net> wrote in message
news:VDxEg.10485$ok5.2712@dukeread01...
> Try Alaska Copper
> http://www.alaskancopper.com/cuni/pdf/9010_seamless_tubing.pdf They have
a
> 90/10 copper/nickel tube that is probably the best material for exposed
> condensers.
>
> You need to do a lot of research to roll your own A/C condenser. The tube
> size and length is a compromise between pressure drop, heat transfer and
oil
> movement. The surface area has to be sufficient to transfer enough heat.
> If it is to long and small diameter the pressure drop will be to high. If
> it is short and large diameter the refrigerant moves to slow so the oil
will
> drop out and be trapped in the condenser which will starve the compressor
of
> lubrication.
>
> --
> Glenn Ashmore
>
> I'm building a 45' cutter in strip/composite. Watch my progress (or lack
> there of) at: http://www.rutuonline.com
> Shameless Commercial Division: http://www.spade-anchor-us.com
>
> "MarshallE" <meakes DeleteThis @triad.rr.com> wrote in message
> news:jdtEg.34926$so3.22800@southeast.rr.com...
> > Hi,
> >
> > What is the normal metal tubing used for keel coolers and how long
should
> > it
> > last?
> >
> > I am having a heck of a time locating a seawater condenser and have
about
> > decided to make from scratch.
> >
> > I want to A/C using 5 tons for my boat.
> >
> > thanks for help and opinions,
> >
> > Marshall
> >
> >
>
>
 >> Stay informed about: copper tubing and sea/salt water 

MarshallE wrote:

> I want to A/C using 5 tons for my boat.
> Marshall

Hi Marshal:
I hate to sound obvious here, but why dont you call up a marine refer
guy in TX or LA that services the shrimp or oilfiled fleets. Time is
money. Send him $50 bucks.
Bob
 >> Stay informed about: copper tubing and sea/salt water