I guess I m either trying to re invent the wheel or to think out of the box ...

Using a little DC blower to extract heat from the ER doesn't really do anything... blowing air directly from outside isn't a great idea as it just brings a ton of corrosion which I don't want to do on new reman engines and new air cons

So, I m thinking of using 120v squirrel blowers pulling air from the genny room into each ER. Even if in the 250/300 cfm range there is plenty of opening thru the ER vents so that the ERs don't get pressurized and leak ER air into the staterooms.

The air flow thru the genny room would also help cool it. What am I missing ?

Many larger boats use AC blowers to pump air into the ER, I like the idea