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[Reason: Added info on wiring to 24V power.]

The pilot berth is arguably the best berth for passages due to reduced pitching and yawing movement.  It is handy at other times as well.  HOWEVER it can also be the worst berth on the boat because it ends up being the hottest place in the boat (second only to a recently used engine room).   This is due to lack of flow through ventilation and solar heat from the deck and cockpit.  Mount a fan in there and it just blows the hot air around--absolutely 100% terrible in hot climates.  IMHO the theory of flowing air from the hatches in the bow and salon and through the berth/passageway and out the aft hatch just doesn't work and you also end up with a lot of pre-heated air flowing into the aft cabin. 

First a few plugs regarding Caframo Sirocco II 3-Speed 7" Gimbal Fans.  They are quiet, they move a lot of air and they are gimbaled and can be pointed anywhere, even reversed to draw air out, they have timers for 3,6,9,12 hours and they use little energy-- 24V draw is: 0.06 amp for 90cfm, 0.11 amp for 114 cfm and  0.17 amp for 140 cfm.

We created a solution which we think is effective by mounting inside the berth passagway porthole.  Best explained by photos and be sure to watch the video--  https://photos.app.goo.gl/7htPWGVA3kNkQTAV8   It works by pulling outside air in and can be aimed effectively and again it pulls in a large amount of air.  Out off the way (especially because people lean outward for head clearance as they transit the area) and looks like it would belong there, easy wiring from the fuel gauge to the engine room for 24V.  Mount it so the 45degree detent is just shy of touching (and vibrating) against the open port.  It was easy to run 24V from the forward end of the catch-all along with the wires to the fuel gauge and into the engineroom and over to the 24V terminals on the forward bulkhead of the engineroom.  At lease one of the photos shows the off-white cord hider that we used to neaten up the installation and protect the power line-- https://www.amazon.com/gp/product/B07Y9VPHHX/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1  The wall ito the cockpit is thin there so we used #6 round headed stainless through mounted screws to mount it and the nuts on these machine screw are what the bracket is mounted to--it is important to size the length of the machine screws so that there is clearance in the bracket when the fan is slid onto it.  This was easy except due to electrical wires the bottom of the 6 mounting screws was not used.  We drilled the holes small enough that the machine screws needed to be screwed through the wall and just sealed them with a bit of silicon--I doubt they will ever leak a drop.  The small rounded screw heads attract no "what is that?" attention in the cockpit-- https://photos.app.goo.gl/ze5VNbUP5bag7xYS7  A side note:  you can aim it straight parallel with the boat if you are running AC and want to pull cold air into the area.

Salon--ALSO I added a couple of Sirocco fans (with all of their advantages) to the salon.....  you can wire from your salon lamps and they look like they should be there (at lease I think so) and DO NOT pull air from the hot top of the salon--again, MUCH quieter than Hella, etc fans.  Photos show them in locked positions and flat agains the bulkhead  https://photos.app.goo.gl/RTDT11j3WHxnmG7q7

 

As good as I think the pilot berth fan is, it is the 2nd best fan on the boat.  By far the most important fan is in the aft cabin.  If you click the link below you can see one of 2 posts I made about a Sirocco extraction fan on the aft room hatch--most IMPORTANT fan on the boat.  I heartily recommend it.  https://amelyachtowners.groups.io/g/main/message/61304

Cheers,
Bob and Suzanne       KAIMI SM429