Merchantman Fan Housing

jankers · 01-07-2007

There is a Fan House abaft the wheelhouse and for'ard of the funnel on this 1950's ship.

This appears to be in two sections, or at least have some type of indent into what would otherwise be a normal block superstructure.

Does anyone have any info on this type of housing, where they induction or exhaust units? Also, are mushroom vents normally induction or exhaust?

J.

**Bunkerbarge** · 01-07-2007

You don't have a bigger picture do you Jankers? I can't tell much from that.

More generally the curved horn type of fitting is an inlet. Originally rotatable so that it could be pointed into the wind. These remained a similar shape when fans were introduced and still used as inlets.

Outlets would usually be less obvious and may not even exist at all, simply relying on escaping air pressue from around the space in general. This arrangement would be found where forced draught was required such as in machinery spaces etc.

The Mushroom type of fitting is usually a vent and not part of a forced draught arrangement. You may find these on tanks or cargo spaces and are simply to allow the space to breath rather than over or under pressurise.

jankers · 01-07-2007

Thanks Richard,

Sadly, that is the best pic i have, all the side elevations are masked
by boats.

From what you say, would i be correct in assuming that the fan house structure
would be part of a forced draught system, therefore an induction?, on which case the apparent indent in the house must be the air inlet?

Or have i missed the point completly?

J.

**Bunkerbarge** · 01-07-2007

It's so difficult to say without seeing any more of it but, yes it could be part of a "Fan Room" and the indent could be some sort of filter arrangement or moisture eliminators which could be made more effective by increasing the available surface area.

It could also be the Captains bathroom from what we can see of it!!

jankers · 02-07-2007

Bunkerbarge,

Indeed it could, but the plan says it is a "fan housing" so i guess it is, then again the plan isn't the best in the world!

Other model makers have chosen to model it with differing designs, any (or none) of which could be correct. My design will be different again so, perhaps, one of us will get it right.

J.