If you have a small cabin on a boat can you get a small heat exchanger
that heats in winter and cools in summer that runs on 12 volts? What
kind of system would you use?

wrote in message
...
If you have a small cabin on a boat can you get a small heat exchanger
that heats in winter and cools in summer that runs on 12 volts? What
kind of system would you use?


No.

Eisboch

On Jan 29, 8:24*pm, "Eisboch" wrote:
wrote in message

...

If you have a small cabin on a boat can you get a small heat exchanger
that heats in winter and cools in summer that runs on 12 volts? What
kind of system would you use?

No.

Eisboch

So how do they air condition boats and campers?

On Thu, 29 Jan 2009 17:32:38 -0800 (PST),
wrote:

On Jan 29, 8:24*pm, "Eisboch" wrote:
wrote in message

...

If you have a small cabin on a boat can you get a small heat exchanger
that heats in winter and cools in summer that runs on 12 volts? What
kind of system would you use?

No.

Eisboch

So how do they air condition boats and campers?

My air conditioner in the travel trailer requires 110volts. The built in
heater is propane fired, although there is a heating element in the A/C for
taking the chill off.

We take a small electric heater on trips and use the electricity we've paid
for from the campground.
--
John H

For a great time, go here first... http://tinyurl.com/d3vxvm

* Definition of a teenager?
God's punishment...for enjoying sex. *

wrote:
On Jan 29, 8:24 pm, "Eisboch" wrote:
wrote in message

...

If you have a small cabin on a boat can you get a small heat exchanger
that heats in winter and cools in summer that runs on 12 volts? What
kind of system would you use?
No.

Eisboch

So how do they air condition boats and campers?


When you say "air condition," I assume you mean cool and heat.

There are several ways to do either on a boat through separate systems
or both through a device like a home heat pump.


The current draw can be substantial. Some boats have systems that can
only be used when the craft is tied up at the dock and using shore
power. Some boats have generators that provide all the power that is
needed. I suppose a compressor can be hooked up to a boat's main engine
for AC, but I've not seen that, and it would require the main to be running.

The first Parker I ever saw, at a Florida boat show, had an AC unit on
the cabin roof. Looked like a unit from a camper. It was driven by
dockside electrical power.


Heat can be simpler. Heat from the engine's cooling system can be
radiated into the cabin through air or water heat transfer so you have
heat as long as the engine is running.

wrote in message
...
On Jan 29, 8:24 pm, "Eisboch" wrote:
wrote in message

...

If you have a small cabin on a boat can you get a small heat exchanger
that heats in winter and cools in summer that runs on 12 volts? What
kind of system would you use?

No.

Eisboch

So how do they air condition boats and campers?

My smart ass answer was because you said "runs on 12 volts". You would
have to have a battery bank the size of the boat to have enough amp capacity
to run a heater or air conditioner for very long. A small AC unit will draw
roughly 8 amps at 120 volts, so figure more than 10 times that using a 12
volt compressor (if they made one) or running it from a 12vdc to 120vac
inverter.

Generating enough heat BTU's would be a similar current draw. 12 volts is
simply unrealistic.

Air conditioners on boats or campers run from either 120 volts and in rare
cases, 220 volts.
The power is supplied from a genset or shore power.

Campers usually have either a heat strip in the AC unit and/or propane
heating systems.

Eisboch

Eisboch wrote:

wrote in message
...
On Jan 29, 8:24 pm, "Eisboch" wrote:
wrote in message

...

If you have a small cabin on a boat can you get a small heat exchanger
that heats in winter and cools in summer that runs on 12 volts? What
kind of system would you use?

No.

Eisboch

So how do they air condition boats and campers?

My smart ass answer was because you said "runs on 12 volts". You would
have to have a battery bank the size of the boat to have enough amp
capacity to run a heater or air conditioner for very long. A small AC
unit will draw roughly 8 amps at 120 volts, so figure more than 10 times
that using a 12 volt compressor (if they made one) or running it from a
12vdc to 120vac inverter.

Generating enough heat BTU's would be a similar current draw. 12 volts
is simply unrealistic.

Air conditioners on boats or campers run from either 120 volts and in
rare cases, 220 volts.
The power is supplied from a genset or shore power.

Campers usually have either a heat strip in the AC unit and/or propane
heating systems.

Eisboch


Heat pumps too.

"Jim749293432" wrote in message
...
Eisboch wrote:

wrote in message
...
On Jan 29, 8:24 pm, "Eisboch" wrote:
wrote in message

...

If you have a small cabin on a boat can you get a small heat exchanger
that heats in winter and cools in summer that runs on 12 volts? What
kind of system would you use?

No.

Eisboch

So how do they air condition boats and campers?

My smart ass answer was because you said "runs on 12 volts". You would
have to have a battery bank the size of the boat to have enough amp
capacity to run a heater or air conditioner for very long. A small AC
unit will draw roughly 8 amps at 120 volts, so figure more than 10 times
that using a 12 volt compressor (if they made one) or running it from a
12vdc to 120vac inverter.

Generating enough heat BTU's would be a similar current draw. 12 volts
is simply unrealistic.

Air conditioners on boats or campers run from either 120 volts and in
rare cases, 220 volts.
The power is supplied from a genset or shore power.

Campers usually have either a heat strip in the AC unit and/or propane
heating systems.

Eisboch


Heat pumps too.


Forgot that. Reverse cycle combination AC and Heat. But not for 12vdc.

Eisboch

On Thu, 29 Jan 2009 21:54:02 -0500, "Eisboch"
wrote:


wrote in message
...
On Jan 29, 8:24 pm, "Eisboch" wrote:
wrote in message

...

If you have a small cabin on a boat can you get a small heat exchanger
that heats in winter and cools in summer that runs on 12 volts? What
kind of system would you use?

No.

Eisboch

So how do they air condition boats and campers?

My smart ass answer was because you said "runs on 12 volts". You would
have to have a battery bank the size of the boat to have enough amp capacity
to run a heater or air conditioner for very long. A small AC unit will draw
roughly 8 amps at 120 volts, so figure more than 10 times that using a 12
volt compressor (if they made one) or running it from a 12vdc to 120vac
inverter.

Generating enough heat BTU's would be a similar current draw. 12 volts is
simply unrealistic.

Air conditioners on boats or campers run from either 120 volts and in rare
cases, 220 volts.
The power is supplied from a genset or shore power.

Campers usually have either a heat strip in the AC unit and/or propane
heating systems.

Propane heat and maybe something like this for 12V A/C.
http://www.arcticbreeze-truckac.com/...eezeintro.html

But you're still going to need a genset for the A/C unless you have
120v service and an inverter.
Might be better/cheaper then to go with cheap 120v home window unit.
Larry has recommended these kind of setups and you can google his
solutions.
The Mac 26 forum had a number of guys installing A/C, and they all
went the shore power/genset 120v window unit route.
See what the ice-fishing guys uses to heat their ice shacks.
I know nothing about heat pumps, except the temp differentials often
make them non-cost effective.

--Vic

"Vic Smith" wrote in message
...


wrote in message
...

If you have a small cabin on a boat can you get a small heat exchanger
that heats in winter and cools in summer that runs on 12 volts? What
kind of system would you use?

Propane heat and maybe something like this for 12V A/C.
http://www.arcticbreeze-truckac.com/...eezeintro.html

But you're still going to need a genset for the A/C unless you have
120v service and an inverter.
Might be better/cheaper then to go with cheap 120v home window unit.
Larry has recommended these kind of setups and you can google his
solutions.

The Mac 26 forum had a number of guys installing A/C, and they all
went the shore power/genset 120v window unit route.
See what the ice-fishing guys uses to heat their ice shacks.
I know nothing about heat pumps, except the temp differentials often
make them non-cost effective.

--Vic

I installed a residential, 10,000 BTU window AC unit in the
rear hatch of the Grand Banks we had. Kept the aft cabin nice and
comfortable for sleeping on hot, humid nights. Roughly 200 bucks,
including the marine plywood I bought to mount it in.
A marine AC unit, mounted in the engine room and ducted to the cabins was
quoted at about $6k to $8K by the guys at the marina. For the number of
times we needed AC up here, it wasn't worth the expense. Obviously, it was
used only when docked and when plugged into shore power, although I could
have run it while underway off the generator.

My current boat has two reverse cycle AC/heat units. The Navigator had
four of them. Marine types exchange using water rather than ambient air and
surprisingly, there is still enough heat in the ocean water up here during
the winter for them to produce enough heat to keep the boat nice and warm.
I usually shut them down and winterized them before the deep cold set in.
If I had stayed on the boat all winter, like some others do at our marina,
I'd would have used them throughout the entire winter. I know a few people
that live on their boats year-round at the marina and they have told me that
there is only about a 2 week period in the middle of the winter when they
have to supplement the heat pumps with some electric space heaters.

Eisboch