Author Topic: Ducting outlet from saloon  (Read 3550 times)

elias

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Ducting outlet from saloon
« on: September 24 2022, 15:15 »
Hi to all !
Again your inspiration … I am trying to figure where to put a duct pipe that will collect the heat from the fridge compressor and from a small 24v air con that I might try to install . I was thinking to channel  the heat to the engine room that is insulated from the rest of the boat and will have a blower to reject it while motoring.
The duct pipe will be around 11cm diameter .
Another alternative I was thinking will be the air vent located near the base of the mast but I m worried for the aesthetics .
Any other had that experience ?

Jake

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Re: Ducting outlet from saloon
« Reply #1 on: September 24 2022, 15:26 »
Running duct work to the engine compartment will be difficult, especially with large ducting.  The air conditioning unit will function better if it's water cooled.  It's much easier to plumb another thru hull than to chop up the interior to run ducting.

I installed insulation on the bottom of the fridge to isolate it from the heat generated by the cooling unit.

Jake
Jake Brodersen
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Bavaria 44

SYJetzt

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Re: Ducting outlet from saloon
« Reply #2 on: September 24 2022, 15:43 »
The way to remove the heat from the fridge compressor cabinet is to fit a water cooled self pumping system as available from indel webasto. A fridge technician removed  the quick connect fittings from the webasto standard fittings and soldered  these ones used by dometic, filled the sp fitting with r134 gas ( the connect fittings of Indel and Dometic unfortunately are not compatible)  I Drilled a new hole in the hull ( approx. 30 cm lower than the existing one) for the kitchen sink to mount the sp fitting below waterline. Left the existing air cooler of the cooling unit  in place, but connected the sp fitting between compressor and air cooler. This modification brought down the temperature in the cooling unit cabinet significantly, and the consumption of energy from 90Ah down to 40Ah per day.

elias

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Re: Ducting outlet from saloon
« Reply #3 on: September 24 2022, 17:03 »
I did that with the insulation at the bottom of the fridge

SYJetzt

So the gas is still circulating through the air cooler ? Wouldn’t that create pressure problems in the circuit on the future ?

SYJetzt

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Re: Ducting outlet from saloon
« Reply #4 on: September 24 2022, 21:56 »
No, it does not, because the air cooler is in the part of system, where the coolant gas is in its liquid form. It losts its temperature mainly in the sp fitting, leaving only less temperature for the air cooler, hence less temperature in cabinet. But first(before fitting the sp fitting) i isolated the fridge bottom too, which was also an improvement.

elias

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Re: Ducting outlet from saloon
« Reply #5 on: September 29 2022, 19:45 »
Sounds very good , and I guess when on land you can still use the fridge with the fan system right ?

SYJetzt

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Re: Ducting outlet from saloon
« Reply #6 on: October 01 2022, 21:05 »
I didn't check this, but it seems possible.

ancanc

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Re: Ducting outlet from saloon
« Reply #7 on: September 15 2023, 20:53 »
Hi, SYJetzt, I was considering to buy the SP condenser for the fridge too, they look good. Do you have good experience with it after a whole season? (or you installed it already earlier?) Any problems with fouling? I imagine fouling could block the small holes in the condenser and stop the heat exchange. OK you have a fallback solution through the original condenser - which is a very good solution, I did not come to the idea of installing booth of them.
Frigoboat is offering some other types of condensers, called "keel-cooler", these are placed completely outside the hull.
What I do not understand, why is it not possible to use the boats keel itself to cool the compressed fridge gas down, this is usually a very big piece of iron cooled from the water on a big surface. If the heat would go into it through the keel bolts it would probably raise the temperature of the - lets say - 3 tons keel by 0,1 degree - if at all,  I imagine.  Or would it be a security issue "heating" the keel bolts?