HOW TO: Caframo Sirocco II 12 volt Marine Cabin Fan

[John E Davies]

 

I had been using a 120 volt desk top Vornado fan (which was very effective, though a little bulky) but I wanted a built-in one that used less power and did not require continually running the inverter. This is the well regarded Caframo Sirocco II, made in Canada. The price varies a little, I bought it when it got down to $100.

 

https://smile.amazon.com/gp/product/B01LDY4TE4/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1

 

It has three speeds and a "time delay off" function. Amp draw from the small DC motor is very minimal: Low: 0.12 amp, Medium: 0.22 amp, High: 0.35 amp (at 12 volts). Max airflow is 140 cubic feet per minute on High. That is not nearly as much as the Vornado on Low, but it is plenty adequate.

 

I had already removed the fixed TV and mount from the back curbside corner, so I mounted the fan there. Since there were already 4 big holes, plugged by the original screws, I did not want to drill any extras. I made a plate out of 6061-T6 1/8" thick aluminum plate, attached the fan mounting plate to that with rivets, and bolted the plate to the bottom of the cabinet using two of those big screws.A future owner could remove the fan without leaving behind any extra cavities... and the location is good for sleepers and does not get in the way when folded up.

 

The fan mounting bracket is designed to mount to a flat surface, then you slide the fan sideways onto the plastic studs and secure it with two long machine screws. I used common long 1/8" diameter aluminum pop rivets.

 

 

Because each rivet head was down inside a cavity, I added a teeny nut to the shank before pulling it.

 

 

The back side of each rivet hole was countersunk most of the way through the material:

 

 

I used a small flat pin punch in the vise and a bigger one on top of the tail to drive it into the countersunk part:

 

 

And ground each tail flush using a little Dremel grinder with a sanding disc:

 

 

By grinding the tails flush, they would not damage the nice gelcoat of the overhead cabinet. Here is the assembly screwed in place:

 

 

John Davies

 

Spokane WA

 

 

[John E Davies]

Attach the supplied wire harness and electronic noise filter. I ran into a problem here; one of the nuts would not go onto a stud. After a couple of minutes of fumbling and some bad words I realized that it had no internal threads. So I went down to Ace Hardware and found a couple of new ones: size M4-.7. These are really fine thread and may be hard to find locally if you are unlucky enough to need any. Here is the hookup:

 

 

The wires run out the side slot then up through the TV cable hole into the overhead. I used a white spiral wrap protective sleeve on the two wires and secured them to the cabinet with a short "service loop" using a stick-on wire mount. I spliced into a power and ground wire that supplied the 12 volt round receptacle there, adding a 3 amp mini blade inline fuse in the power wire.

 

 

I then added some labels with a black Sharpie so I would know what was what:

 

 

The gimbaled mount allows you to swivel the airflow in any direction. If I want to crack open the rear window for ventilation the fan will draw that air into the cabin. For working around the bed you can fold it up and out of the way.

 

 

Nifty.

 

John Davies

 

Spokane WA

 

 

 

 

[KenB]

I bought two of the same fan sometime this winter. They are currently sitting out in the camper.  Occasionally I hold them up to the wall, try different mounting spots/orientations, and then try to work up the gumption to drill new holes into the fiberglass. Still hasn’t happened.

 

Your location is one of my prime choices. Seeing the base mounted perpendicular to the side wall makes sense. You can easily see the controls and LEDs in that orientation.

 

My plan was to mount it with through bolts using the two counter sunk holes provided and a backing plate on the other side. Your six rivets are not part of the factory mounting suggestion, but should be good insurance against coming loose while the trailer bounces down the road.

 

I wonder which is worse for loosening mounted fixtures like this fan, pounding waves in a boat, or bumpy roads?

 

Thanks for the ideas.

 

Ken

[John E Davies]

Ken, I don’t think using just the two center screws with a backing plate behind would be nearly strong enough. That would be a lot of stress on two small fasteners. By riveting the plastic backing plate the load is shared evenly by six fasteners, not counting those two great big honking 1/4” screws that used to hold the TV up.

 

I do plan to leave the fan locked in the down position normally, that will place less stress on the cam lock mechanism when towing. Most of the parts are plastic, I think the fan will hold up OK but I would not take chances with it.

 

John Davies

 

Spokane WA

[mossemi]

I couldn’t decide where to mount my fan, so I put it on a piece of oak I had and we move it around a needed.

[SeaDawg]

Nice fan, and nice installation. Practical Sailor tests marine fans periodically, and Caframo fans are always in the recommendations. Quiet, powerful, energy efficient.

Btw, they tested one of your style in 2008. In an update in June 2017, the fan was still running. Roughly 9 years of daily use...

 

 

Sherry

[John E Davies]

Thanks for the review, I had not seen that one. I used to get Practical Sailor in print years before there was an Internet. Having access to all the digital back issues would be a great benefit. I no longer do more than occasionally paddle a canoe, though it would be tempting to read unbiased reviews about marine products and boats.

 

John Davies

 

Spokane WA

[hobo]

John,

 

Did the noise filter come with the fan or did you purchase that separately?  Sorry if I missed any previous comments on that point.  Nice install.

[John E Davies]

On 1/10/2020 at 3:59 AM, hobo said:

John,

 

Did the noise filter come with the fan or did you purchase that separately?  Sorry if I missed any previous comments on that point.  Nice install.

The filter came preinstalled on the fan harness. I am not sure it is needed on a travel trailer, but for a marine installation near a com radio it would be needed, I think. Because it has a DC motor with brushes, it does send out a little radio noise, but the filter kills that.

The fan has worked out well, it doesn’t move a ton of air but it is adequate, even on Low. It’s a DANDY unit.  Highly recommended.

John Davies

Spokane WA

Edited November 30, 2020 by John E Davies