Ventilation

Because the marina where we keep Northern Lights II charges $.21 per kWh I started last year trying to make the boat more comfortable in summer. To keep from using the A/C units I added a couple of 12v fans, a Caframo Sirocco in the master berth and a Hella Turbo that can be directed to the solon or galley. They do a excellent job of moving air thru the boat whether in the slip or while anchored out. The Sirocco is mounted just forward of the hatch over the bed and can be positioned to move air thru the hatch in either direction. Now I find this new hatch fan from Caframo a Taku, 2013 Pittman Innovation Award Winner Caframo Taku Hatch Fan | Sail Magazine
I like everything about it except how to power it when the hatch screen is in place. Has anyone bought and used a Taku yet and what's your experience with it? I still want to add another fan to the guest berth I was leaning towards a Hella Turbo because it wouldn't be used much and it's cheaper than the Caframo but I believe the caframo is a higher quality fan.

Greetings,
Mr. RC. Put a grommet in the screen and feed the wire through.

Or some black silicone (or whatever color the screen material is).

Nice fan...
Most people I know take a 10 inch or if lucky and can find an 18 inch box fan and mount it to some plywood cut to fit the hatch...

Granted they are 110V but still very low power and pretty efficient at moving air. The also tend to be quieter than 12V fans because of blade size, speed, design...but I'm sure newer 12V marine fans have a lot of design makeovers all the time.

Did you consider solar powered fans, obviating the need for cords and no power consumption..? I have a smaller SolarVent version in my for'd hatch, but there are much bigger more powerful ones now available. They only work in daylight of course, but we have one in our home roof space and it needs very little light to get moving - and fast. You might find a US distributor for these..

Solar Star - Roof Ventilation - Solatube Australia

Following on from Pete, here is one of the RM1200 mounted on a Bomar hatch. The hatch can still open. No wires to run, although I suspect you could add some if you wanted it to run at night also. They can move a lot of air.....

Dunno about cost comparisons, but the DC fans are probably still using some 110 source when at a marina -- albeit with a few more steps involved.

FWIW, our AC units allow independent control of the fans (air handlers), so we can move a lot of air with those even while the compressors (and water pump) are turned off. Probably lower power consumption, not sure how much.

-Chris

ranger42c said:

FWIW, our AC units allow independent control of the fans (air handlers), so we can move a lot of air with those even while the compressors (and water pump) are turned off. Probably lower power consumption, not sure how much.

-Chris

Click to expand...

Our 15k BTU Cruisair unit can operate in fan mode only. Tried it the other day when it was hot, but not hot enough to use the A/C. It pulled about 9 amps on low speed and about 14 on high using the inverter.

The fan in the berth is for use mostly at night so that would eliminate the solar powered as a choice. I never saw the large solar powered fans the only ones I've seen are the smaller versions for use in a head. The large hatch size units would be excellent for daytime use to move air thru a boat while anchored. Can the direction of flow be changed on the larger units? Thank you for all the replies

Ron check to see if the larger ones come with a rechargeable battery. Our 4" fan has a solar panel that both operates the fan in the daytime and runs the fan through the night.

dwhatty said:

Our 15k BTU Cruisair unit can operate in fan mode only. Tried it the other day when it was hot, but not hot enough to use the A/C. It pulled about 9 amps on low speed and about 14 on high using the inverter.

Click to expand...

And presumably that compares favorably to when the compressor and water pump are running for actual AC?

I could check stuff like that next time I'm down there...

-Chris

ranger42c said:

And presumably that compares favorably to when the compressor and water pump are running for actual AC?

-Chris

Click to expand...

Not sure about that. Definitely need 110 (gen or shore power) to start the A/C. Never tried turning off the 110 and going to inverter once A/C is running to see what the draw might be.

Bay Pelican said:

Ron check to see if the larger ones come with a rechargeable battery. Our 4" fan has a solar panel that both operates the fan in the daytime and runs the fan through the night.

Click to expand...

Here is the US site for the large solar fans.
Solar Star Solar-powered Attic Ventilation Systems | Solatube

I don't think any come with a battery, but the IM 1200 has the fan and solar panel as separate components so putting a battery in the middle would be straightforward. Maybe you could also have a switch on the fan-side of the circuit to reverse polarity to the fan motor, and reverse the flow direction?

Bay Pelican said:

Ron check to see if the larger ones come with a rechargeable battery. Our 4" fan has a solar panel that both operates the fan in the daytime and runs the fan through the night.

Click to expand...

I think this is what you had in mind.

Defender.com Search Results: solar vent

dwhatty said:

Our 15k BTU Cruisair unit can operate in fan mode only. Tried it the other day when it was hot, but not hot enough to use the A/C. It pulled about 9 amps on low speed and about 14 on high using the inverter.

Click to expand...

Hmmm...

On our 16K BTU Marine Air Vector Compact units:
- one unit, fan only, low (1) = 1+ amp
- one unit, fan only, high (6) = 2+ amps
- one AC and pump + fan low = 12 amps
- one AC and pump + fan high = 13 amps
- start-up of one AC and pump pegs the ammeter briefly
- startup of second AC (pump already running), no big deal

These AC amp readings from the analog ammeter at our distribution panel. (Straight AC shorepower, no inverter involved.)

One or two amps for each fan only, maybe not such a big deal.

Soft start is a good thing.

-Chris

Welcome to Fan-Tastic Vent!

www.fantasticvent.com/
Fan-Tastic manufactures built-in and portable vents for use in RVs. Photos, features, specifications, installation instructions, FAQ, and vendors.

RV unit fits in std RV hole , very quiet at lower speeds , rain sensor will close it as required.Low power use.

Back in the day cruising down island the hassle was IF you went ashore and left the hatch open it would be sure to rain.

The cruisers Automatic Hatch Closer is the answer.

Install a block of wood in the fwd corner of the hatch with a 1/4 inch hole in it.

Place a cheapo aspirin over the hole and stand a chop stick on the aspirin to prop up the hatch.

Rain no problem , but it wont automatically open as the Fantastic unit will.

Folks with Dorade vents can use 12v muffin fans to move air.

The 24V is great on 12v , still moves air with a gentle breeze and no noise at all.

Beware you will need to reverse them if you wish both in and out .

Our method is to use 6 inch plastic deck plates on the inside under the Dorade.

It will seal if the Dorade is swept away , and 2 extra covers one for 12v intake , one for 24 v intake as its over the masters bunk and a gale is not needed at all times.

The ears are hacked off the muffin fans and a hole cut in the cover , then hot glued to assemble.