And now...wiring a 12v DC computor fan.

[pcatterall]

My hopes of using a 12v domestic fan (to drag cooler air into my boat via a vent) are dashed as I had not realised that it would be AC not DC.
As several of you have told me... it will be cheaper to get a DC fan rather than try to convert.
Well ... I have got a computor fan which will fit up my 'vent hole'.

It is 12 v DC and my only problem is the wiring blue red black and yellow I have no idea which to wire up. I suspect that there may be 2 speeds and possibly a thermostat wire but will appreciate some help.

I have some doubts as to the power of this fan to reall bring much air into the boat though it is quoted as around 40 cubic feet per minute.

I have been searching for a more powerful fan but so far have only seen the bilge blower type which have the power but wont fit the 4 inch vent.

 

[sarabande]

btw how long is the trunking this fan is intended for. If it is more than 4 ft and higher at the outlet, you maight bet soem benefit from free "stack effect".

 

[pcatterall]

At this time I want to see if I can get a decent through flow of air by using the exiting roof vents.
These only have about 3 inches of 'tube' but I can accomodate a unit which protrudes a little through the cabin roof as these vents arnt anywhere where heads may be banged!

 

[Heckler]

My hopes of using a 12v domestic fan (to drag cooler air into my boat via a vent) are dashed as I had not realised that it would be AC not DC.
As several of you have told me... it will be cheaper to get a DC fan rather than try to convert.
Well ... I have got a computor fan which will fit up my 'vent hole'.

It is 12 v DC and my only problem is the wiring blue red black and yellow I have no idea which to wire up. I suspect that there may be 2 speeds and possibly a thermostat wire but will appreciate some help.

I have some doubts as to the power of this fan to reall bring much air into the boat though it is quoted as around 40 cubic feet per minute.

I have been searching for a more powerful fan but so far have only seen the bilge blower type which have the power but wont fit the 4 inch vent.

black and red is obvious, the yellow is the speed sensor
Stu

 

[Keith-i]

and I think blue is to control the speed via a frequency controller on the pc motherboard.

 

[pcatterall]

Thanks guys.
And Stu..... have we found a good use for all those redundant D2 fan motors?
( I suspect that the computor fan is ok just to circulate air but not my requirement which is to drag in that cool evening air and push out the hot stuff!!)

 

[eagleswing]

12v dc fan additions..

we improved the livability of our 33' sailboat significantly by adding 4 'caframo' 12v ventilating fans mounted on the underside of the coach roofs--1 in each of the cabins, close to each dorade vent outlet. The fan blade assembly is rotatable to suck air in or blow air out of a particular vent . Two of the fancier fans have 2-4-6-8 hour timers, and 3 speed controls, so they can be set to turn off automatically in the middle of the night when the temperature has cooled down. they are a very low amp draw too. these fans are one of the best improvements we've ever made as it has been almost as hot as the 7th circle of hell here in the USA 100 degrees F 32 degrees C this summer.. These Caframos are exceptionally well made by Canadian Fan Co... hope they are available across the great pond ?

 

[Ecartar]

DC Fan

Have a look at www.farnell.com. You should be spoilt for choice...........